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Sample records for response stress response

  1. 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

  2. Stress Responses of Shewanella

    PubMed Central

    Yin, Jianhua; Gao, Haichun

    2011-01-01

    The shewanellae are ubiquitous in aquatic and sedimentary systems that are chemically stratified on a permanent or seasonal basis. In addition to their ability to utilize a diverse array of terminal electron acceptors, the microorganisms have evolved both common and unique responding mechanisms to cope with various stresses. This paper focuses on the response and adaptive mechanism of the shewanellae, largely based on transcriptional data. PMID:21912550

  3. Metabolomics for plant stress response.

    PubMed

    Shulaev, Vladimir; Cortes, Diego; Miller, Gad; Mittler, Ron

    2008-02-01

    Stress in plants could be defined as any change in growth condition(s) that disrupts metabolic homeostasis and requires an adjustment of metabolic pathways in a process that is usually referred to as acclimation. Metabolomics could contribute significantly to the study of stress biology in plants and other organisms by identifying different compounds, such as by-products of stress metabolism, stress signal transduction molecules or molecules that are part of the acclimation response of plants. These could be further tested by direct measurements, correlated with changes in transcriptome and proteome expression and confirmed by mutant analysis. In this review, we will discuss recent application of metabolomics and system biology to the area of plant stress response. We will describe approaches such as metabolic profiling and metabolic fingerprinting as well as combination of different 'omics' platforms to achieve a holistic view of the plant response stress and conduct detailed pathway analysis.

  4. Staphylococcal response to oxidative stress

    PubMed Central

    Gaupp, Rosmarie; Ledala, Nagender; Somerville, Greg A.

    2012-01-01

    Staphylococci are a versatile genus of bacteria that are capable of causing acute and chronic infections in diverse host species. The success of staphylococci as pathogens is due in part to their ability to mitigate endogenous and exogenous oxidative and nitrosative stress. Endogenous oxidative stress is a consequence of life in an aerobic environment; whereas, exogenous oxidative and nitrosative stress are often due to the bacteria's interaction with host immune systems. To overcome the deleterious effects of oxidative and nitrosative stress, staphylococci have evolved protection, detoxification, and repair mechanisms that are controlled by a network of regulators. In this review, we summarize the cellular targets of oxidative stress, the mechanisms by which staphylococci sense oxidative stress and damage, oxidative stress protection and repair mechanisms, and regulation of the oxidative stress response. When possible, special attention is given to how the oxidative stress defense mechanisms help staphylococci control oxidative stress in the host. PMID:22919625

  5. Plant Responses to Nanoparticle Stress.

    PubMed

    Hossain, Zahed; Mustafa, Ghazala; Komatsu, Setsuko

    2015-11-06

    With the rapid advancement in nanotechnology, release of nanoscale materials into the environment is inevitable. Such contamination may negatively influence the functioning of the ecosystems. Many manufactured nanoparticles (NPs) contain heavy metals, which can cause soil and water contamination. Proteomic techniques have contributed substantially in understanding the molecular mechanisms of plant responses against various stresses by providing a link between gene expression and cell metabolism. As the coding regions of genome are responsible for plant adaptation to adverse conditions, protein signatures provide insights into the phytotoxicity of NPs at proteome level. This review summarizes the recent contributions of plant proteomic research to elaborate the complex molecular pathways of plant response to NPs stress.

  6. 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.

  7. 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

  8. Auxin response under osmotic stress.

    PubMed

    Naser, Victoria; Shani, Eilon

    2016-08-01

    The phytohormone auxin (indole-3-acetic acid, IAA) is a small organic molecule that coordinates many of the key processes in plant development and adaptive growth. Plants regulate the auxin response pathways at multiple levels including biosynthesis, metabolism, transport and perception. One of the most striking aspects of plant plasticity is the modulation of development in response to changing growth environments. In this review, we explore recent findings correlating auxin response-dependent growth and development with osmotic stresses. Studies of water deficit, dehydration, salt, and other osmotic stresses point towards direct and indirect molecular perturbations in the auxin pathway. Osmotic stress stimuli modulate auxin responses by affecting auxin biosynthesis (YUC, TAA1), transport (PIN), perception (TIR/AFB, Aux/IAA), and inactivation/conjugation (GH3, miR167, IAR3) to coordinate growth and patterning. In turn, stress-modulated auxin gradients drive physiological and developmental mechanisms such as stomata aperture, aquaporin and lateral root positioning. We conclude by arguing that auxin-mediated growth inhibition under abiotic stress conditions is one of the developmental and physiological strategies to acclimate to the changing environment.

  9. Plant Responses to Nanoparticle Stress

    PubMed Central

    Hossain, Zahed; Mustafa, Ghazala; Komatsu, Setsuko

    2015-01-01

    With the rapid advancement in nanotechnology, release of nanoscale materials into the environment is inevitable. Such contamination may negatively influence the functioning of the ecosystems. Many manufactured nanoparticles (NPs) contain heavy metals, which can cause soil and water contamination. Proteomic techniques have contributed substantially in understanding the molecular mechanisms of plant responses against various stresses by providing a link between gene expression and cell metabolism. As the coding regions of genome are responsible for plant adaptation to adverse conditions, protein signatures provide insights into the phytotoxicity of NPs at proteome level. This review summarizes the recent contributions of plant proteomic research to elaborate the complex molecular pathways of plant response to NPs stress. PMID:26561803

  10. 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.

  11. Stress disrupts response memory retrieval.

    PubMed

    Guenzel, Friederike M; Wolf, Oliver T; Schwabe, Lars

    2013-08-01

    Stress effects on memory are well-known. Most studies, however, focused on the impact of stress on hippocampus-dependent 'declarative' memory processes. Less is known about whether stress influences also striatum-based memory processes, such as stimulus-response (S-R) memory. First evidence from rodent experiments shows that glucocorticoid stress hormones may enhance the consolidation of S-R memories. Whether stress affects also S-R memory retrieval remains largely elusive. Therefore, we tested in the present experiment in humans the effect of stress on the retrieval of S-R memories. Healthy men and women were trained to locate three objects in an S-R version of a virtual eight-arm radial maze. One week later, participants underwent a stressor or a control condition before their memory of the S-R task was tested. Our results showed that participants (n=43) who were exposed to the stressor before retention testing made significantly more errors in this test trial, suggesting that stress impaired S-R memory retrieval. Moreover, high cortisol concentrations were associated with reduced S-R memory. These findings indicate that stress may affect memory retrieval processes in humans beyond hippocampal 'declarative' memory.

  12. Plant responses to flooding stress.

    PubMed

    Loreti, Elena; van Veen, Hans; Perata, Pierdomenico

    2016-10-01

    Most plant species cannot survive prolonged submergence or soil waterlogging. Crops are particularly intolerant to the lack of oxygen arising from submergence. Rice can instead germinate and grow even if submerged. The molecular basis for rice tolerance was recently unveiled and will contribute to the development of better rice varieties, well adapted to flooding. The oxygen sensing mechanism was also recently discovered. This system likely operates in all plant species and relies on the oxygen-dependent destabilization of the group VII ethylene response factors (ERFVIIs), a cluster of ethylene responsive transcription factors. An homeostatic mechanism that controls gene expression in plants subjected to hypoxia prevents excessive activation of the anaerobic metabolism that could be detrimental to surviving the stress.

  13. 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…

  14. Endoplasmic Reticulum Stress Response in Arabidopsis Roots

    PubMed Central

    Cho, Yueh; Kanehara, Kazue

    2017-01-01

    Roots are the frontier of plant body to perceive underground environmental change. Endoplasmic reticulum (ER) stress response represents circumvention of cellular stress caused by various environmental changes; however, a limited number of studies are available on the ER stress responses in roots. Here, we report the tunicamycin (TM) -induced ER stress response in Arabidopsis roots by monitoring expression patterns of immunoglobulin-binding protein 3 (BiP3), a representative marker for the response. Roots promptly responded to the TM-induced ER stress through the induction of similar sets of ER stress-responsive genes. However, not all cells responded uniformly to the TM-induced ER stress in roots, as BiP3 was highly expressed in root tips, an outer layer in elongation zone, and an inner layer in mature zone of roots. We suggest that ER stress response in roots has tissue specificity. PMID:28298914

  15. Stress response to laparoscopic liver resection

    PubMed Central

    Ueda, Kazuki; Turner, Patricia

    2004-01-01

    Background: The magnitude of the systemic response is proportional to the degree of surgical trauma. Much has been reported in the literature comparing metabolic and immune responses, analgesia use, or length of hospital stay between laparoscopic and open procedures. In particular, metabolic and immune responses are represented by measuring various chemical mediators as stress responses. Laparoscopic procedures are associated with reduced operative trauma compared with open procedures, resulting in lower systemic response. As a result, laparoscopic procedures are now well accepted for both benign and malignant processes. Laparoscopic liver resection, specifically, is employed for symptomatic and some malignant tumors, following improvements in diagnostic accuracy, laparoscopic devices, and techniques. However, laparoscopic liver resection is still controversial in malignant disease because of complex anatomy, the technical difficulty of the procedure, and questionable indications. There are few reports describing the stress responses associated with laparoscopic liver resection, even though many studies reviewing stress responses have been performed recently in both humans and animal models comparing laparoscopic to conventional open surgery. Although this review examines stress response after laparoscopic liver resection in both an animal and human clinical model, further controlled randomized studies with additional investigations of immunologic parameters are needed to demonstrate the consequences of either minimally invasive surgery or open procedures on perioperative or postoperative stress responses for laparoscopic liver resection. PMID:18333082

  16. Process Control Minitoring by Stress Response

    SciTech Connect

    Hazen, Terry C.; Stahl, David A.

    2006-04-17

    Environmental contamination with a variety of pollutants hasprompted the development of effective bioremediation strategies. But howcan these processes be best monitored and controlled? One avenue underinvestigation is the development of stress response systems as tools foreffective and general process control. Although the microbial stressresponse has been the subject of intensive laboratory investigation, theenvironmental reflection of the laboratory response to specific stresseshas been little explored. However, it is only within an environmentalcontext, in which microorganisms are constantly exposed to multiplechanging environmental stresses, that there will be full understanding ofmicrobial adaptive resiliency. Knowledge of the stress response in theenvironment will facilitate the control of bioremediation and otherprocesses mediated by complex microbial communities.

  17. Pediatric Perioperative Stress Responses and Anesthesia

    PubMed Central

    Yuki, Koichi; Matsunami, Erika; Tazawa, Kazumasa; Wang, Wei; DiNardo, James A.; Koutsogiannaki, Sophia

    2017-01-01

    Summary Surgical stress responses cause an array of endocrinological, metabolic and immunological changes in patients. The landmark studies in the 1980s showed that adequate anesthesia dramatically improved the outcomes of pediatric surgical patients by attenuating stress hormonal responses, pointing out the harm of ‘inadequate’ anesthesia. Subsequent studies questioned the role of administering very high-dose anesthetics to further attenuate stress responses. Here we review the feature of surgical stress responses in pediatric patients including their difference from those in adult patients. Overall, pediatric patients show minimal or no resting energy expenditure change postoperatively. In adult patients, increased resting energy expenditure has been described. Pediatric patients demonstrated robust cortisol and catecholamine responses than adult patients. However, the duration of these surges is often short-lived. Systemic proinflammatory and anti-inflammatory cytokine levels have been measured. Pediatric patients showed less proinflammatory cytokine elevation, but had similar anti-antiinflamatory responses. We also review in detail the immunological changes in response to surgical stress. Based on our current knowledge, we attempted to understand the underlying mechanism how adequate anesthesia dramatically improved the outcome of patients. Although more work is needed to be done, understanding how pediatric patients respond to perioperative stress, and its mechanism and consequence will allow us to direct us into a better, perioperative management in this population. PMID:28217718

  18. The hyperosmotic stress response of Campylobacter jejuni

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The hyperosmotic stress response of Campylobacter jejuni: The diarrheal pathogen Campylobacter jejuni and other gastrointestinal bacteria encounter changes in osmolarity in the environment, through exposure to food processing, or upon entering host organisms, where osmotic adaptation can be associa...

  19. Delayed Stress Response Syndrome: Family Therapy Indications

    ERIC Educational Resources Information Center

    Figley, Charles R.; Sprenkle, Douglas H.

    1978-01-01

    The delayed stress response syndrome is a form of chronic catastrophic stress disorder. The theoretical nature of the syndrome and its most characteristic symptoms are delineated within the context of treating Vietnam combat veterans. The paper outlines treatment implications within a family therapy program. (Author)

  20. Response of Desulfovibrio vulgaris to alkaline stress.

    PubMed

    Stolyar, Sergey; He, Qiang; Joachimiak, Marcin P; He, Zhili; Yang, Zamin Koo; Borglin, Sharon E; Joyner, Dominique C; Huang, Katherine; Alm, Eric; Hazen, Terry C; Zhou, Jizhong; Wall, Judy D; Arkin, Adam P; Stahl, David A

    2007-12-01

    The response of exponentially growing Desulfovibrio vulgaris Hildenborough to pH 10 stress was studied using oligonucleotide microarrays and a study set of mutants with genes suggested by microarray data to be involved in the alkaline stress response deleted. The data showed that the response of D. vulgaris to increased pH is generally similar to that of Escherichia coli but is apparently controlled by unique regulatory circuits since the alternative sigma factors (sigma S and sigma E) contributing to this stress response in E. coli appear to be absent in D. vulgaris. Genes previously reported to be up-regulated in E. coli were up-regulated in D. vulgaris; these genes included three ATPase genes and a tryptophan synthase gene. Transcription of chaperone and protease genes (encoding ATP-dependent Clp and La proteases and DnaK) was also elevated in D. vulgaris. As in E. coli, genes involved in flagellum synthesis were down-regulated. The transcriptional data also identified regulators, distinct from sigma S and sigma E, that are likely part of a D. vulgaris Hildenborough-specific stress response system. Characterization of a study set of mutants with genes implicated in alkaline stress response deleted confirmed that there was protective involvement of the sodium/proton antiporter NhaC-2, tryptophanase A, and two putative regulators/histidine kinases (DVU0331 and DVU2580).

  1. Response of Desulfovibrio vulgaris to Alkaline Stress

    SciTech Connect

    Stolyar, S.; He, Q.; He, Z.; Yang, Z.; Borglin, S.E.; Joyner, D.; Huang, K.; Alm, E.; Hazen, T.C.; Zhou, J.; Wall, J.D.; Arkin, A.P.; Stahl, D.A.

    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 three 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).

  2. Epigenetic responses to stress: triple defense?

    PubMed

    Gutzat, Ruben; Mittelsten Scheid, Ortrun

    2012-11-01

    Stressful conditions for plants can originate from numerous physical, chemical and biological factors, and plants have developed a plethora of survival strategies including developmental and morphological adaptations, specific signaling and defense pathways as well as innate and acquired immunity. While it has become clear in recent years that many stress responses involve epigenetic components, we are far from understanding the mechanisms and molecular interactions. Extending our knowledge is fundamental, not least for plant breeding and conservation biology. This review will highlight recent insights into epigenetic stress responses at the level of signaling, chromatin modification, and potentially heritable consequences.

  3. Protein Degradation and the Stress Response

    PubMed Central

    Flick, Karin; Kaiser, Peter

    2012-01-01

    Environmental stresses are manifold and so are the responses they elicit. This is particularly true for higher eukaryotes where various tissues and cell types are differentially affected by the insult. Type and scope of the stress response can therefore differ greatly among cell types. Given the importance of the Ubiquitin Proteasome System (UPS) for most cellular processes, it comes as no surprise that the UPR plays a pivotal role in counteracting the effects of stressors. Here we outline contributions of the UPS to stress sensing, signaling, and response pathways. We make no claim to comprehensiveness but choose selected examples to illustrate concepts and mechanisms by which protein modification with ubiquitin and proteasomal degradation of key regulators ensures cellular integrity during stress situations. PMID:22414377

  4. Proteasome stress responses in Schistosoma mansoni.

    PubMed

    de Paula, Renato Graciano; de Magalhães Ornelas, Alice Maria; Morais, Enyara Rezende; de Souza Gomes, Matheus; de Paula Aguiar, Daniela; Magalhães, Lizandra Guidi; Rodrigues, Vanderlei

    2015-05-01

    The proteasome proteolytic system is the major ATP-dependent protease in eukaryotic cells responsible for intracellular protein turnover. Schistosoma mansoni has been reported to contain an ubiquitin-proteasome proteolytic pathway, and many studies have suggested a biological role of proteasomes in the development of this parasite. Additionally, evidence has suggested diversity in proteasome composition under several cellular conditions, and this might contribute to the regulation of its function in this parasite. The proteasomal system has been considered important to support the protein homeostasis during cellular stress. In this study, we described in vitro effects of oxidative stress, heat shock, and chemical stress on S. mansoni adults. Our findings showed that chemical stress induced with curcumin, IBMX, and MG132 modified the gene expression of the proteasomal enzymes SmHul5 and SmUbp6. Likewise, the expression of these genes was upregulated during oxidative stress and heat shock. Analyses of the S. mansoni life cycle showed differential gene expression in sporocysts, schistosomulae, and miracidia. These results suggested that proteasome accessory proteins participate in stress response during the parasite development. The expression level of SmHul5 and SmUbp6 was decreased by 16-fold and 9-fold, respectively, by the chemical stress induced with IBMX, which suggests proteasome disassembly. On the other hand, curcumin, MG132, oxidative stress, and heat shock increased the expression of these genes. Furthermore, the gene expression of maturation proteasome protein (SmPOMP) was increased in stress conditions induced by curcumin, MG132, and H₂O₂, which could be related to the synthesis of new proteasomes. S. mansoni adult worms were found to utilize similar mechanisms to respond to different conditions of stress. Our results demonstrated that oxidative stress, heat shock, and chemical stress modified the expression profile of genes related to the ubiquitin

  5. Proteomics studies on stress responses in diatoms.

    PubMed

    Muhseen, Ziyad Tariq; Xiong, Qian; Chen, Zhuo; Ge, Feng

    2015-12-01

    Diatoms are a highly diverse group of eukaryotic phytoplankton that are distributed throughout marine and freshwater environments and are believed to be responsible for approximately 40% of the total marine primary productivity. The ecological success of diatoms suggests that they have developed a range of strategies to cope with various biotic and abiotic stress factors. It is of great interest to understand the adaptive responses of diatoms to different stresses in the marine environment. Proteomic technologies have been applied to the adaptive responses of marine diatoms under different growth conditions in recent years such as nitrogen starvation, iron limitation and phosphorus deficiency. These studies have provided clues to elucidate the sophisticated sensing mechanisms that control their adaptive responses. Although only a very limited number of proteomic studies were conducted in diatoms, the obtained data have led to a better understanding of the biochemical processes that contribute to their ecological success. This review presents the current status of proteomic studies of diatom stress responses and discusses the novel developments and applications for the analysis of protein post-translational modification in diatoms. The potential future application of proteomics could contribute to a better understanding of the physiological mechanisms underlying diatom acclimation to a given stress and the acquisition of an enhanced diatom stress tolerance. Future challenges and research opportunities in the proteomics studies of diatoms are also discussed.

  6. Biological responses of audiogenic stress

    NASA Astrophysics Data System (ADS)

    Mathur, R.; Behari, J.; Sharma, K. N.

    1986-12-01

    Biological effects of prolonged exposure to sound waves (˜17 kHz) on developing female rats were examined. Rat pups of day 80 were grouped into two. Experimental group was exposed to sound waves and control group, who were not so exposed. Daily food, water intake were measured in developing animals and spontaneous motor activity, electrocardiogram and blood sugar were studied in adults. It was found that the experimental group of animals behaved differently from the control group. It is concluded that the sound waves produced changes in the animals which were within the physiological limits but were suggestive of development of stress.

  7. Stress responses in yeasts: what rules apply?

    PubMed

    González-Párraga, Pilar; Sánchez-Fresneda, Ruth; Martínez-Esparza, María; Argüelles, Juan-Carlos

    2008-04-01

    Living organisms have evolved a complex network of mechanisms to face the unforeseen nutritional and environmental circumstances imposed on their natural habitats, commonly termed "stress". To learn more about these mechanisms, several challenges are usually applied in the laboratory, namely nutrient starvation, heat shock, dehydration, oxidative exposures, etc. Yeasts are chosen as convenient models for studying stress phenomena because of their simple cellular organization and the amenability to genetic analysis. A vast scientific literature has recently appeared on the defensive cellular responses to stress. However, this plethora of studies covers quite different experimental conditions, making any conclusions open to dispute. In fact, the term "yeast stress" is rather confusing, since the same treatment may be very stressful or irrelevant, depending on the yeast. Customary expressions such as "gentle stress" (non-lethal) or "severe stress" (potentially lethal) should be precisely clarified. In turn, although prototypic yeasts share a common repertoire of signalling responsive pathways to stress, these are adapted to the specific ecological niche and biological activity of each particular species. What does "stress" really mean? Before we go any deeper, we have to define this uncertain meaning along with a proper explanation concerning the terms and conditions used in research on yeast stress.

  8. The Adaptive Calibration Model of stress responsivity

    PubMed Central

    Ellis, Bruce J.; Shirtcliff, Elizabeth A.

    2010-01-01

    This paper presents the Adaptive Calibration Model (ACM), an evolutionary-developmental theory of individual differences in the functioning of the stress response system. The stress response system has three main biological functions: (1) to coordinate the organism’s allostatic response to physical and psychosocial challenges; (2) to encode and filter information about the organism’s social and physical environment, mediating the organism’s openness to environmental inputs; and (3) to regulate the organism’s physiology and behavior in a broad range of fitness-relevant areas including defensive behaviors, competitive risk-taking, learning, attachment, affiliation and reproductive functioning. The information encoded by the system during development feeds back on the long-term calibration of the system itself, resulting in adaptive patterns of responsivity and individual differences in behavior. Drawing on evolutionary life history theory, we build a model of the development of stress responsivity across life stages, describe four prototypical responsivity patterns, and discuss the emergence and meaning of sex differences. The ACM extends the theory of biological sensitivity to context (BSC) and provides an integrative framework for future research in the field. PMID:21145350

  9. 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.

  10. Response

    ERIC Educational Resources Information Center

    Higgins, Chris

    2012-01-01

    This article presents the author's response to the reviews of his book, "The Good Life of Teaching: An Ethics of Professional Practice." He begins by highlighting some of the main concerns of his book. He then offers a brief response, doing his best to address the main criticisms of his argument and noting where the four reviewers (Charlene…

  11. A humoral stress response in Drosophila.

    PubMed

    Ekengren, S; Tryselius, Y; Dushay, M S; Liu, G; Steiner, H; Hultmark, D

    2001-05-01

    The ability to react to unfavorable environmental changes is crucial for survival and reproduction, and several adaptive responses to stress have been conserved during evolution [1-3]. Specific immune and heat shock responses mediate the elimination of invading pathogens and of damaged proteins or cells [4-6]. Furthermore, MAP kinases and other signaling factors mediate cellular responses to a very broad range of environmental insults [7-9]. Here we describe a novel systemic response to stress in Drosophila. The Turandot A (TotA) gene encodes a humoral factor, which is secreted from the fat body and accumulates in the body fluids. TotA is strongly induced upon bacterial challenge, as well as by other types of stress such as high temperature, mechanical pressure, dehydration, UV irradiation, and oxidative agents. It is also upregulated during metamorphosis and at high age. Strikingly, flies that overexpress TotA show prolonged survival and retain normal activity at otherwise lethal temperatures. Although TotA is only induced by severe stress, it responds to a much wider range of stimuli than heat shock genes such as hsp70 or immune genes such as Cecropin A1.

  12. Stress responses in lactic acid bacteria.

    PubMed

    van de Guchte, Maarten; Serror, Pascale; Chervaux, Christian; Smokvina, Tamara; Ehrlich, Stanislav D; Maguin, Emmanuelle

    2002-08-01

    Lactic acid bacteria (LAB) constitute a heterogeneous group of bacteria that are traditionally used to produce fermented foods. The industrialization of food bio-transformations increased the economical importance of LAB, as they play a crucial role in the development of the organoleptique and hygienic quality of fermented products. Therefore, the reliability of starter strains in terms of quality and functional properties (important for the development of aroma and texture), but also in terms of growth performance and robustness has become essential. These strains should resist to adverse conditions encountered in industrial processes, for example during starter handling and storage (freeze-drying, freezing or spray-drying). The development of new applications such as life vaccines and probiotic foods reinforces the need for robust LAB since they may have to survive in the digestive tract, resist the intestinal flora, maybe colonize the digestive or uro-genital mucosa and express specific functions under conditions that are unfavorable to growth (for example, during stationary phase or storage). Also in nature, the ability to quickly respond to stress is essential for survival and it is now well established that LAB, like other bacteria, evolved defense mechanisms against stress that allow them to withstand harsh conditions and sudden environmental changes. While genes implicated in stress responses are numerous, in LAB the levels of characterization of their actual role and regulation differ widely between species. The functional conservation of several stress proteins (for example, HS proteins, Csp, etc) and of some of their regulators (for example, HrcA, CtsR) renders even more striking the differences that exist between LAB and the classical model micro-organisms. Among the differences observed between LAB species and B. subtilis, one of the most striking is the absence of a sigma B orthologue in L. lactis ssp. lactis as well as in at least two streptococci

  13. Oxidative stress response in Paracoccidioides brasiliensis.

    PubMed

    Campos, Elida G; Jesuino, Rosália Santos Amorim; Dantas, Alessandra da Silva; Brígido, Marcelo de Macedo; Felipe, Maria Sueli S

    2005-06-30

    Survival of pathogenic fungi inside human hosts depends on evasion from the host immune system and adaptation to the host environment. Among different insults that Paracoccidioides brasiliensis has to handle are reactive oxygen and nitrogen species produced by the human host cells, and by its own metabolism. Knowing how the parasite deals with reactive species is important to understand how it establishes infection and survives within humans. The initiative to describe the P. brasiliensis transcriptome fostered new approaches to study oxidative stress response in this organism. By examining genes related to oxidative stress response, one can evaluate the parasite's ability to face this condition and infer about possible ways to overcome this ability. We report the results of a search of the P. brasiliensis assembled expressed sequence tag database for homologous sequences involved in oxidative stress response. We described several genes coding proteins involved in antioxidant defense, for example, catalase and superoxide dismutase isoenzymes, peroxiredoxin, cytochrome c peroxidase, glutathione synthesis enzymes, thioredoxin, and the transcription factors Yap1 and Skn7. The transcriptome analysis of P. brasiliensis reveals a pathogen that has many resources to combat reactive species. Besides characterizing the antioxidant defense system in P. brasiliensis, we also compared the ways in which different fungi respond to oxidative damage, and we identified the basic features of this response.

  14. Responses of succulents to plant water stress.

    PubMed

    Hanscom, Z; Ting, I P

    1978-03-01

    Experiments were performed to test the hypothesis that succulents "shift" their method of photosynthetic metabolism in response to environmental change. Our data showed that there were at least three different responses of succulents to plant water status. When plant water status of Portulacaria afra (L.) Jacq. was lowered either by withholding water or by irrigating with 2% NaCl, a change from C(3)-photosynthesis to Crassulacean acid metabolism (CAM) occurred. Fluctuation of titratable acidity and nocturnal CO(2) uptake was induced in the stressed plants. Stressed Peperomia obtusifolia A. Dietr. plants showed a change from C(3)-photosynthesis to internal cycling of CO(2). Acid fluctuation commenced in response to stress but exogenous CO(2) uptake did not occur. Zygocactus truncatus Haworth plants showed a pattern of acid fluctuation and nocturnal CO(2) uptake typical of CAM even when well irrigated. The cacti converted from CAM to an internal CO(2) cycle similar to Peperomia when plants were water-stressed. Reverse phase gas exchange in succulents results in low water loss to carbon gain. Water is conserved and low levels of metabolic activity are maintained during drought periods by complete stomatal closure and continual fluctuation of organic acids.

  15. Human Cardiovascular Responses to Passive Heat Stress

    PubMed Central

    Crandall, Craig G.; Wilson, Thad E.

    2016-01-01

    Heat stress increases human morbidity and mortality compared to normothermic conditions. Many occupations, disease states, as well as stages of life are especially vulnerable to the stress imposed on the cardiovascular system during exposure to hot ambient conditions. This review focuses on the cardiovascular responses to heat stress that are necessary for heat dissipation. To accomplish this regulatory feat requires complex autonomic nervous system control of the heart and various vascular beds. For example, during heat stress cardiac output increases up to twofold, by increases in heart rate and an active maintenance of stroke volume via increases in inotropy in the presence of decreases in cardiac preload. Baroreflexes retain the ability to regulate blood pressure in many, but not all, heat stress conditions. Central hypovolemia is another cardiovascular challenge brought about by heat stress, which if added to a subsequent central volumetric stress, such as hemorrhage, can be problematic and potentially dangerous, as syncope and cardiovascular collapse may ensue. These combined stresses can compromise blood flow and oxygenation to important tissues such as the brain. It is notable that this compromised condition can occur at cardiac outputs that are adequate during normothermic conditions but are inadequate in heat because of the increased systemic vascular conductance associated with cutaneous vasodilation. Understanding the mechanisms within this complex regulatory system will allow for the development of treatment recommendations and countermeasures to reduce risks during the ever-increasing frequency of severe heat events that are predicted to occur. PMID:25589263

  16. Sympathoneural and Adrenomedullary Responses to Mental Stress

    PubMed Central

    Carter, Jason R.; Goldstein, David S.

    2017-01-01

    This concept-based review provides historical perspectives and updates about sympathetic noradrenergic and sympathetic adrenergic responses to mental stress. The topic of this review has incited perennial debate, because of disagreements over definitions, controversial inferences, and limited availability of relevant measurement tools. The discussion begins appropriately with Cannon's "homeostasis" and his pioneering work in the area. This is followed by mental stress as a scientific idea and the relatively new notions of allostasis and allostatic load. Experimental models of mental stress in rodents and humans are discussed, with particular attention to ethical constraints in humans. Sections follow on sympathoneural to mental stress, reactivity of catecholamine systems, clinical pathophysiologic states, and the cardiovascular reactivity hypothesis. Future advancement of the field will require integrative approaches and coordinated efforts between physiologists and psychologists on this interdisciplinary topic. PMID:25589266

  17. Hyperosmotic Stress Response of Campylobacter jejuni

    PubMed Central

    Cameron, Andrew; Frirdich, Emilisa; Huynh, Steven; Parker, Craig T.

    2012-01-01

    The diarrheal pathogen Campylobacter jejuni and other gastrointestinal bacteria encounter changes in osmolarity in the environment, through exposure to food processing, and upon entering host organisms, where osmotic adaptation can be associated with virulence. In this study, growth profiles, transcriptomics, and phenotypic, mutant, and single-cell analyses were used to explore the effects of hyperosmotic stress exposure on C. jejuni. Increased growth inhibition correlated with increased osmotic concentration, with both ionic and nonionic stressors inhibiting growth at 0.620 total osmol liter−1. C. jejuni adaptation to a range of osmotic stressors and concentrations was accompanied by severe filamentation in subpopulations, with microscopy indicating septum formation and phenotypic diversity between individual cells in a filament. Population heterogeneity was also exemplified by the bifurcation of colony morphology into small and large variants on salt stress plates. Flow cytometry of C. jejuni harboring green fluorescent protein (GFP) fused to the ATP synthase promoter likewise revealed bimodal subpopulations under hyperosmotic stress. We also identified frequent hyperosmotic stress-sensitive variants within the clonal wild-type population propagated on standard laboratory medium. Microarray analysis following hyperosmotic upshift revealed enhanced expression of heat shock genes and genes encoding enzymes for synthesis of potential osmoprotectants and cross-protective induction of oxidative stress genes. The capsule export gene kpsM was also upregulated, and an acapsular mutant was defective for growth under hyperosmotic stress. For C. jejuni, an organism lacking most conventional osmotic response factors, these data suggest an unusual hyperosmotic stress response, including likely “bet-hedging” survival strategies relying on the presence of stress-fit individuals in a heterogeneous population. PMID:22961853

  18. 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.

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

    SciTech Connect

    Calabrese, Edward J. . E-mail: edwardc@schoolph.umass.edu; 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.

    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.

  20. Physiological Responses to Thermal Stress and Exercise

    NASA Astrophysics Data System (ADS)

    Iyota, Hiroyuki; Ohya, Akira; Yamagata, Junko; Suzuki, Takashi; Miyagawa, Toshiaki; Kawabata, Takashi

    The simple and noninvasive measuring methods of bioinstrumentation in humans is required for optimization of air conditioning and management of thermal environments, taking into consideration the individual specificity of the human body as well as the stress conditions affecting each. Changes in human blood circulation were induced with environmental factors such as heat, cold, exercise, mental stress, and so on. In this study, the physiological responses of human body to heat stress and exercise were investigated in the initial phase of the developmental research. We measured the body core and skin temperatures, skin blood flow, and pulse wave as the indices of the adaptation of the cardiovascular system. A laser Doppler skin blood flowmetry using an optical-sensor with a small portable data logger was employed for the measurement. These results reveal the heat-stress and exercise-induced circulatory responses, which are under the control of the sympathetic nerve system. Furthermore, it was suggested that the activity of the sympathetic nervous system could be evaluated from the signals of the pulse wave included in the signals derived from skin blood flow by means of heart rate variability assessments and detecting peak heights of velocity-plethysmogram.

  1. Stress, stress-induced cortisol responses, and eyewitness identification performance.

    PubMed

    Sauerland, Melanie; Raymaekers, Linsey H C; Otgaar, Henry; Memon, Amina; Waltjen, Thijs T; Nivo, Maud; Slegers, Chiel; Broers, Nick J; Smeets, Tom

    2016-07-01

    In the eyewitness identification literature, stress and arousal at the time of encoding are considered to adversely influence identification performance. This assumption is in contrast with findings from the neurobiology field of learning and memory, showing that stress and stress hormones are critically involved in forming enduring memories. This discrepancy may be related to methodological differences between the two fields of research, such as the tendency for immediate testing or the use of very short (1-2 hours) retention intervals in eyewitness research, while neurobiology studies insert at least 24 hours. Other differences refer to the extent to which stress-responsive systems (i.e., the hypothalamic-pituitary-adrenal axis) are stimulated effectively under laboratory conditions. The aim of the current study was to conduct an experiment that accounts for the contemporary state of knowledge in both fields. In all, 123 participants witnessed a live staged theft while being exposed to a laboratory stressor that reliably elicits autonomic and glucocorticoid stress responses or while performing a control task. Salivary cortisol levels were measured to control for the effectiveness of the stress induction. One week later, participants attempted to identify the thief from target-present and target-absent line-ups. According to regression and receiver operating characteristic analyses, stress did not have robust detrimental effects on identification performance. Copyright © 2016 John Wiley & Sons, Ltd. © 2016 The Authors Behavioral Sciences & the Law Published by John Wiley & Sons Ltd.

  2. Space flight, microgravity, stress, and immune responses

    NASA Astrophysics Data System (ADS)

    Sonnenfeld, G.

    1999-01-01

    Exposure of animals and humans to space flight conditions has resulted in numerous alterations in immunological parameters. Decreases in lymphocyte blastogenesis, cytokine production, and natural killer cell activity have all been reported after space flight. Alterations in leukocyte subset distribution have also been reported after flight of humans and animals in space. The relative contribution of microgravity conditions and stress to the observed results has not been established. Antiorthostatic, hypokinetic, hypodynamic, suspension of rodents and chronic head-down tilt bed-rest of humans have been used to model effects of microgravity on immune responses. After use of these models, some effects of space flight on immune responses, such as decreases in cytokine function, were observed, but others, such as alterations in leukocyte subset distribution, were not observed. These results suggest that stresses that occur during space flight could combine with microgravity conditions in inducing the changes seen in immune responses after space flight. The biological/biomedical significance of space flight induced changes in immune parameters remains to be established.

  3. Stress response and apoptosis in pro- and antiinflammatory macrophages.

    PubMed

    Malyshev, I Yu; Kruglov, S V; Bakhtina, L Yu; Malysheva, E V; Zubin, M; Norkin, M

    2004-08-01

    We showed that stress response and apoptosis in macrophages depend on the phenotype of their secretory activity and specific biological and physical characteristics of the factor inducing stress-response or apoptosis.

  4. Waterborne Risperidone Decreases Stress Response in Zebrafish.

    PubMed

    Idalencio, Renan; Kalichak, Fabiana; Rosa, João Gabriel Santos; de Oliveira, Tiago Acosta; Koakoski, Gessi; Gusso, Darlan; Abreu, Murilo Sander de; Giacomini, Ana Cristina Varrone; Barcellos, Heloísa Helena de Alcântara; Piato, Angelo L; Barcellos, Leonardo José Gil

    2015-01-01

    The presence of drugs and their metabolites in surface waters and municipal effluents has been reported in several studies, but its impacts on aquatic organisms are not yet well understood. This study investigated the effects of acute exposure to the antipsychotic risperidone on the stress and behavioral responses in zebrafish. It became clear that intermediate concentration of risperidone inhibited the hypothalamic-pituitary-interrenal axis and displayed anxiolytic-like effects in zebrafish. The data presented here suggest that the presence of this antipsychotic in aquatic environments can alter neuroendocrine and behavior profiles in zebrafish.

  5. Waterborne Risperidone Decreases Stress Response in Zebrafish

    PubMed Central

    Kalichak, Fabiana; Rosa, João Gabriel Santos; de Oliveira, Tiago Acosta; Koakoski, Gessi; Gusso, Darlan; de Abreu, Murilo Sander; Giacomini, Ana Cristina Varrone; Barcellos, Heloísa Helena de Alcântara

    2015-01-01

    The presence of drugs and their metabolites in surface waters and municipal effluents has been reported in several studies, but its impacts on aquatic organisms are not yet well understood. This study investigated the effects of acute exposure to the antipsychotic risperidone on the stress and behavioral responses in zebrafish. It became clear that intermediate concentration of risperidone inhibited the hypothalamic-pituitary-interrenal axis and displayed anxiolytic-like effects in zebrafish. The data presented here suggest that the presence of this antipsychotic in aquatic environments can alter neuroendocrine and behavior profiles in zebrafish. PMID:26473477

  6. Response to temperature stress in rhizobia.

    PubMed

    Alexandre, Ana; Oliveira, Solange

    2013-08-01

    It is well established that soil is a challenging environment for bacteria, where conditions may change rapidly and bacteria have to acclimate and adapt in order to survive. Rhizobia are an important group of soil bacteria due to their ability to establish atmospheric nitrogen-fixing symbioses with many legume species. Some of these legumes are used to feed either humans or cattle and therefore the use of rhizobia can reduce the need for synthetic N-fertilizers. Several environmental factors shape the composition and the activity of rhizobia populations in the rhizosphere. Soil pH and temperature are often considered to be the major abiotic factors in determining the bacterial community diversity. The present review focuses on the current knowledge on the molecular bases of temperature stress response in rhizobia. The effects of temperature stress in the legume-rhizobia symbioses are also addressed.

  7. Anomalous Stress Response of Ultrahard WBn Compounds

    NASA Astrophysics Data System (ADS)

    Li, Quan; Zhou, Dan; Zheng, Weitao; Ma, Yanming; Chen, Changfeng

    2015-10-01

    Boron-rich tungsten borides are premier prototypes of a new class of ultrahard compounds. Here, we show by first-principles calculations that their stress-strain relations display surprisingly diverse and anomalous behavior under a variety of loading conditions. Most remarkable is the dramatically changing bonding configurations and deformation modes with rising boron concentration in WBn (n =2 , 3, 4), resulting in significantly different stress responses and unexpected indentation strength variations. This novel phenomenon stems from the peculiar structural arrangements in tungsten borides driven by boron's ability to form unusually versatile bonding states. Our results elucidate the intriguing deformation mechanisms that define a distinct type of ultrahard material. These new insights underscore the need to explore unconventional structure-property relations in a broad range of transition-metal light-element compounds.

  8. Anomalous stress response of ultrahard WBn compounds

    DOE PAGES

    Li, Quan; Zhou, Dan; Zheng, Weitao; ...

    2015-10-29

    Boron-rich tungsten borides are premier prototypes of a new class of ultrahard compounds. Here, we show by first-principles calculations that their stress-strain relations display surprisingly diverse and anomalous behavior under a variety of loading conditions. Most remarkable is the dramatically changing bonding configurations and deformation modes with rising boron concentration in WBn (n=2, 3, 4), resulting in significantly different stress responses and unexpected indentation strength variations. This novel phenomenon stems from the peculiar structural arrangements in tungsten borides driven by boron’s ability to form unusually versatile bonding states. Our results elucidate the intriguing deformation mechanisms that define a distinct typemore » of ultrahard material. Here, these new insights underscore the need to explore unconventional structure-property relations in a broad range of transition-metal light-element compounds.« less

  9. Adrenergic Polymorphism and the Human Stress Response

    PubMed Central

    Rao, Fangwen; Zhang, Lian; Wessel, Jennifer; Zhang, Kuixing; Wen, Gen; Kennedy, Brian P.; Rana, Brinda K.; Das, Madhusudan; Rodriguez-Flores, Juan L.; Smith, Douglas W.; Cadman, Peter E.; Salem, Rany M.; Mahata, Sushil K.; Schork, Nicholas J.; Taupenot, Laurent; Ziegler, Michael G.; O’Connor, Daniel T.

    2009-01-01

    Tyrosine hydroxylase (TH) is the rate-limiting enzyme in catecholamine biosynthesis. Does common genetic variation at human TH alter autonomic activity and predispose to cardiovascular disease? We undertook systematic polymorphism discovery at the TH locus, and then tested variants for contributions to sympathetic function and blood pressure. We resequenced 80 ethnically diverse individuals across the TH locus. One hundred seventy-two twin pairs were evaluated for sympathetic traits, including catecholamine production and environmental (cold) stress responses. To evaluate hypertension, we genotyped subjects selected from the most extreme diastolic blood pressure percentiles in the population. Human TH promoter haplotype/reporter plasmids were transfected into chromaffin cells. Forty-nine single nucleotide polymorphisms (SNPs) and one tetranucleotide repeat were discovered, but coding region polymorphism did not account for common phenotypic variation. A block of linkage disequilibrium spanned four common variants in the proximal promoter. Catecholamine secretory traits were significantly heritable, as were stress-induced blood pressure changes. In the TH promoter, significant associations were found for urinary catecholamine excretion, as well as blood pressure response to stress. TH promoter haplotype #2 (TGGG) showed pleiotropy, increasing both norepinephrine excretion and blood pressure during stress. In hypertension, a case–control study (1266 subjects, 53% women) established the effect of C-824T in determination of blood pressure. We conclude that human catecholamine secretory traits are heritable, displaying joint genetic determination (pleiotropy) with autonomic activity and finally with blood pressure in the population. Catecholamine secretion is influenced by genetic variation in the adrenergic pathway encoding catecholamine synthesis, especially at the classically rate-limiting step, TH. The results suggest novel pathophysiological links between a key

  10. Hormonal modulation of the heat shock response: insights from fish with divergent cortisol stress responses.

    PubMed

    LeBlanc, Sacha; Höglund, Erik; Gilmour, Kathleen M; Currie, Suzanne

    2012-01-01

    Acute temperature stress in animals results in increases in heat shock proteins (HSPs) and stress hormones. There is evidence that stress hormones influence the magnitude of the heat shock response; however, their role is equivocal. To determine whether and how stress hormones may affect the heat shock response, we capitalized on two lines of rainbow trout specifically bred for their high (HR) and low (LR) cortisol response to stress. We predicted that LR fish, with a low cortisol but high catecholamine response to stress, would induce higher levels of HSPs after acute heat stress than HR trout. We found that HR fish have significantly higher increases in both catecholamines and cortisol compared with LR fish, and LR fish had no appreciable stress hormone response to heat shock. This unexpected finding prevented further interpretation of the hormonal modulation of the heat shock response but provided insight into stress-coping styles and environmental stress. HR fish also had a significantly greater and faster heat shock response and less oxidative protein damage than LR fish. Despite these clear differences in the physiological and cellular responses to heat shock, there were no differences in the thermal tolerance of HR and LR fish. Our results support the hypothesis that responsiveness to environmental change underpins the physiological differences in stress-coping styles. Here, we demonstrate that the heat shock response is a distinguishing feature of the HR and LR lines and suggest that it may have been coselected with the hormonal responses to stress.

  11. Cortisol stress responses and children's behavioral functioning at school

    PubMed Central

    Cillessen, Antonius H.N.; de Weerth, Carolina

    2016-01-01

    The present study investigated whether cortisol stress responses of 6‐year‐olds were associated with their behavioral functioning at school. Additionally, the moderating role of stress in the family environment was examined. To this end, 149 healthy children (M age = 6.09 years; 70 girls) participated in an age‐appropriate innovative social evaluative stress test. Saliva cortisol samples were collected six times during the stress test to calculate two indices of the cortisol stress response: cortisol stress reactivity and total stress cortisol. Teachers assessed children's internalizing, externalizing, and prosocial behaviors. Stress in the family environment was operationalized as maternally reported parenting stress. Results indicated a significant increase in cortisol concentrations in response to the stressor. No significant associations were found between cortisol stress responses and behavioral functioning at school and there was no evidence for moderation by maternal parenting stress. Potential theoretical and methodological explanations for these results are discussed. PMID:27774583

  12. Motivation, stress, and cortisol responses in skydiving.

    PubMed

    Thatcher, Joanne; Reeves, Sue; Dorling, Debbie; Palmer, Anna

    2003-12-01

    This study examined metamotivational dominance, metamotivational states, and cortisol responses in skydiving participants. Data were obtained from 23 experienced skydivers 15 min. prior to and following a skydive. Respondents were mainly paratelic-conformist dominant and most occupied the conformist and arousal-seeking states prior to skydiving, assessed respectively, with Apter, et al.'s Motivational Style Profile and Cook, et al.'s measure of metamotivational states. Paratelic-conformist dominance indicates a predisposition towards conformity and a desire to be spontaneous, and the conformist and arousal seeking states reported prior to completing the skydive represent a desire to conform to expected norms but also to seek arousal. There was no significant change in scores for metamotivational state or stress following skydiving. Contrary to expectations, cortisol level prior to skydiving was negatively associated with external stress. These results support the paratelic, but not the negativistic, dominance found in previous samples of risk sport participants (no skydivers). The conformist dominance and pre-dive conformist metamotivational state scores of this sample may be fundamental for adhering to safety regulations imposed on skydivers. To obtain better understanding of this phenomenon, researchers should attempt to measure these variables during, rather than prior to and after, participation in risk sports.

  13. Effects of cold pressor stress on the human startle response.

    PubMed

    Deuter, Christian E; Kuehl, Linn K; Blumenthal, Terry D; Schulz, André; Oitzl, Melly S; Schachinger, Hartmut

    2012-01-01

    Both emotion and attention are known to influence the startle response. Stress influences emotion and attention, but the impact of stress on the human startle response remains unclear. We used an established physiological stressor, the Cold Pressor Test (CPT), to induce stress in a non-clinical human sample (24 student participants) in a within-subjects design. Autonomic (heart rate and skin conductance) and somatic (eye blink) responses to acoustic startle probes were measured during a pre-stress baseline, during a three minutes stress intervention, and during the subsequent recovery period. Startle skin conductance and heart rate responses were facilitated during stress. Compared to baseline, startle eye blink responses were not affected during the intervention but were diminished afterwards. These data describe a new and unique startle response pattern during stress: facilitation of autonomic stress responses but no such facilitation of somatic startle eye blink responses. The absence of an effect of stress on startle eye blink responsiveness may illustrate the importance of guaranteeing uninterrupted visual input during periods of stress.

  14. Effects of Cold Pressor Stress on the Human Startle Response

    PubMed Central

    Deuter, Christian E.; Kuehl, Linn K.; Blumenthal, Terry D.; Schulz, André; Oitzl, Melly S.; Schachinger, Hartmut

    2012-01-01

    Both emotion and attention are known to influence the startle response. Stress influences emotion and attention, but the impact of stress on the human startle response remains unclear. We used an established physiological stressor, the Cold Pressor Test (CPT), to induce stress in a non-clinical human sample (24 student participants) in a within-subjects design. Autonomic (heart rate and skin conductance) and somatic (eye blink) responses to acoustic startle probes were measured during a pre-stress baseline, during a three minutes stress intervention, and during the subsequent recovery period. Startle skin conductance and heart rate responses were facilitated during stress. Compared to baseline, startle eye blink responses were not affected during the intervention but were diminished afterwards. These data describe a new and unique startle response pattern during stress: facilitation of autonomic stress responses but no such facilitation of somatic startle eye blink responses. The absence of an effect of stress on startle eye blink responsiveness may illustrate the importance of guaranteeing uninterrupted visual input during periods of stress. PMID:23166784

  15. Personality traits modulate emotional and physiological responses to stress

    PubMed Central

    Childs, Emma; White, Tara L.; de Wit, Harriet

    2014-01-01

    An individual’s susceptibility to psychological and physical disorders associated with chronic stress exposure e.g., cardiovascular and infectious disease, may also be predicted by their reactivity to acute stress. One factor associated with both stress resilience and health outcomes is personality. An understanding of how personality influences responses to acute stress may shed light upon individual differences in susceptibility to chronic stress-linked disease. This study examined relationships between personality and acute responses to stress in 125 healthy adults, using hierarchical linear regression. We assessed personality traits using the Multidimensional Personality Questionnaire (MPQ-BF), and responses to acute stress (cortisol, heart rate, blood pressure, mood) using a standardised laboratory psychosocial stress task, the Trier Social Stress Test (TSST). Individuals with high Negative Emotionality exhibited greater emotional distress and lower blood pressure responses to the TSST. Individuals with high Agentic Positive Emotionality exhibited prolonged heart rate responses to stress, whereas those with high Communal Positive Emotionality exhibited smaller cortisol and blood pressure responses. Separate personality traits differentially predicted emotional, cardiovascular, and cortisol responses to a psychosocial stressor in healthy volunteers. Future research investigating the association of personality with chronic stress-related disease may provide further clues to the relationship between acute stress reactivity and susceptibility to disease. PMID:25036730

  16. 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.

  17. Waterborne aripiprazole blunts the stress response in zebrafish

    PubMed Central

    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

    2016-01-01

    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. PMID:27874070

  18. [Individual behavioral and autonomic response to emotional stress in humans].

    PubMed

    Ukraintseva, Iu V; Berlov, D N; Rusalova, M N

    2006-01-01

    Healthy subjects (n = 53) performed a sound version of the proof-reading test under normal conditions and in the state of emotional stress. Stress resistance was evaluated by the overall number of errors. The propensity to active or passive response to stress was evaluated by the number of "false alarms" and signal omissions. The reaction pattern to emotional stress in stress-resistant subjects, irrespective of their behavioral features, consisted in an increase in sympathetic effects on the cardiac rhythm and a decrease in the reaction time to significant signals. In subjects with low stress resistance, no statistically significant changes in the level of sympathetic tone and reaction time were revealed in the state of stress. Subjects with active behavioral response to stress, irrespective of their level of stress resistance, were characterized by aggressiveness, boldness and independence. Subjects with passive response to stress were inclined to conformism, dependence, and passivity.

  19. Affirmation of personal values buffers neuroendocrine and psychological stress responses.

    PubMed

    Creswell, J David; Welch, William T; Taylor, Shelley E; Sherman, David K; Gruenewald, Tara L; Mann, Traci

    2005-11-01

    Stress is implicated in the development and progression of a broad array of mental and physical health disorders. Theory and research on the self suggest that self-affirming activities may buffer these adverse effects. This study experimentally investigated whether affirmations of personal values attenuate physiological and psychological stress responses. Eighty-five participants completed either a value-affirmation task or a control task prior to participating in a laboratory stress challenge. Participants who affirmed their values had significantly lower cortisol responses to stress, compared with control participants. Dispositional self-resources (e.g., trait self-esteem and optimism) moderated the relation between value affirmation and psychological stress responses, such that participants who had high self-resources and had affirmed personal values reported the least stress. These findings suggest that reflecting on personal values can keep neuroendocrine and psychological responses to stress at low levels. Implications for research on the self, stress processes, health, and interventions are discussed.

  20. 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

  1. 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.

  2. 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

  3. Regulation of Stress Responses and Translational Control by Coronavirus

    PubMed Central

    Fung, To Sing; Liao, Ying; Liu, Ding Xiang

    2016-01-01

    Similar to other viruses, coronavirus infection triggers cellular stress responses in infected host cells. The close association of coronavirus replication with the endoplasmic reticulum (ER) results in the ER stress responses, which impose a challenge to the viruses. Viruses, in turn, have come up with various mechanisms to block or subvert these responses. One of the ER stress responses is inhibition of the global protein synthesis to reduce the amount of unfolded proteins inside the ER lumen. Viruses have evolved the capacity to overcome the protein translation shutoff to ensure viral protein production. Here, we review the strategies exploited by coronavirus to modulate cellular stress response pathways. The involvement of coronavirus-induced stress responses and translational control in viral pathogenesis will also be briefly discussed. PMID:27384577

  4. 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

  5. Role of shame and body esteem in cortisol stress responses.

    PubMed

    Lupis, Sarah B; Sabik, Natalie J; Wolf, Jutta M

    2016-04-01

    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.

  6. My stress, our stress: blunted cortisol response to stress in isolated housed zebrafish.

    PubMed

    Giacomini, Ana Cristina Vendrametto Varrone; de Abreu, Murilo Sander; Koakoski, Gessi; Idalêncio, Renan; Kalichak, Fabiana; Oliveira, Thiago Acosta; da Rosa, João Gabriel Santos; Gusso, Darlan; Piato, Angelo Luis; Barcellos, Leonardo José Gil

    2015-02-01

    Here, we show that individually housed zebrafish presented a reduced cortisol response to an acute stressor (persecution with a pen net for 120 s) compared to zebrafish housed in groups of 10. We hypothesized that the cortisol response to stress was reduced in individually housed zebrafish because they depend solely on their own perceptions of the stressor, whereas among grouped zebrafish, the stress response might be augmented by chemical and/or behavioral cues from the other members of the shoal. This hypothesis was based on previous described chemical communication of stress in fish as well on individual variation in stressor perception and potential individual differences in fish personality.

  7. Measuring Physiological Stress Responses in Children: Lessons from a Novice

    ERIC Educational Resources Information Center

    Quas, Jodi A.

    2011-01-01

    In this article the author describes challenges associated with integrating physiological measures of stress into developmental research, especially in the domains of memory and cognition. An initial critical challenge concerns how to define stress, which can refer to one or a series of events, a response, the consequence of that response, an…

  8. The response to inositol: regulation of glycerolipid metabolism and stress response signaling in yeast

    PubMed Central

    Henry, Susan A.; Gaspar, Maria L.; Jesch, Stephen A.

    2014-01-01

    This article focuses on discoveries of the mechanisms governing the regulation of glycerolipid metabolism and stress response signaling in response to the phospholipid precursor, inositol. The regulation of glycerolipid lipid metabolism in yeast in response to inositol is highly complex, but increasingly well understood, and the roles of individual lipids in stress response are also increasingly well characterized. Discoveries that have emerged over several decades of genetic, molecular and biochemical analyses of metabolic, regulatory and signaling responses of yeast cells, both mutant and wild type, to the availability of the phospholipid precursor, inositol are discussed. PMID:24418527

  9. 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

  10. 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.

  11. Habitual Response to Stress in Recovering Adolescent Anorexic Patients

    ERIC Educational Resources Information Center

    Miller, Samantha P.; Erickson, Sarah J.; Branom, Christina; Steiner, Hans

    2009-01-01

    Objective: Although previous research has investigated the stress response in acutely anorexic patients, there is currently little research addressing this response in recovering adolescent anorexic girls. Therefore, this study investigated partially and fully weight-restored anorexic adolescent girls' psychological and physiological response to a…

  12. Stress Response and Translation Control in Rotavirus Infection

    PubMed Central

    López, Susana; Oceguera, Alfonso; Sandoval-Jaime, Carlos

    2016-01-01

    The general stress and innate immune responses are closely linked and overlap at many levels. The outcomes of these responses serve to reprogram host expression patterns to prevent viral invasions. In turn, viruses counter attack these cell responses to ensure their replication. The mechanisms by which viruses attempt to control host cell responses are as varied as the number of different virus families. One of the most recurrent strategies used by viruses to control the antiviral response of the cell is to hijack the translation machinery of the host, such that viral proteins are preferentially synthesized, while the expression of the stress and antiviral responses of the cell are blocked at the translation level. Here, we will review how rotaviruses, an important agent of acute severe gastroenteritis in children, overcome the stress responses of the cell to establish a productive infectious cycle. PMID:27338442

  13. 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 (Mage = 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.

  14. 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.

  15. 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.

  16. 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

  17. Molecular mechanisms of the plant heat stress response

    SciTech Connect

    Qu, Ai-Li; Ding, Yan-Fei; Jiang, Qiong; Zhu, Cheng

    2013-03-08

    Highlights: ► This review elaborates the response networks of heat stress in plants. ► It elaborates proteins responding to heat stress in special physiological period. ► The proteins and pathways have formed a basic network of the heat stress response. ► Achievements of the various technologies are also combined. -- Abstract: High temperature has become a global concern, which seriously affects the growth and production of plants, particularly crops. Thus, the molecular mechanism of the heat stress response and breeding of heat-tolerant plants is necessary to protect food production and ensure crop safety. This review elaborates on the response networks of heat stress in plants, including the Hsf and Hsp response pathways, the response of ROS and the network of the hormones. In addition, the production of heat stress response elements during particular physiological periods of the plant is described. We also discuss the existing problems and future prospects concerning the molecular mechanisms of the heat stress response in plants.

  18. The Replication Stress Response in Pancreatic Cancer

    DTIC Science & Technology

    2013-10-01

    replication and/or DNA damage responses, including FANCI , BRCA2, PKP2, and CTBP2, demonstrating that our screen can yield genes involved in the RSR. We...pii] 10.1016/j.molcel.2009.06.021 (2009). 5. Smogorzewska, A. et al. Identification of the FANCI protein, a monoubiquitinated FANCD2 paralog

  19. Cell-autonomous stress responses in innate immunity.

    PubMed

    Moretti, Julien; Blander, J Magarian

    2017-01-01

    The innate immune response of phagocytes to microbes has long been known to depend on the core signaling cascades downstream of pattern recognition receptors (PRRs), which lead to expression and production of inflammatory cytokines that counteract infection and induce adaptive immunity. Cell-autonomous responses have recently emerged as important mechanisms of innate immunity. Either IFN-inducible or constitutive, these processes aim to guarantee cell homeostasis but have also been shown to modulate innate immune response to microbes and production of inflammatory cytokines. Among these constitutive cell-autonomous responses, autophagy is prominent and its role in innate immunity has been well characterized. Other stress responses, such as metabolic stress, the ER stress/unfolded protein response, mitochondrial stress, or the DNA damage response, seem to also be involved in innate immunity, although the precise mechanisms by which they regulate the innate immune response are not yet defined. Of importance, these distinct constitutive cell-autonomous responses appear to be interconnected and can also be modulated by microbes and PRRs, which add further complexity to the interplay between innate immune signaling and cell-autonomous responses in the mediation of an efficient innate immune response.

  20. Computations of uncertainty mediate acute stress responses in humans.

    PubMed

    de Berker, Archy O; Rutledge, Robb B; Mathys, Christoph; Marshall, Louise; Cross, Gemma F; Dolan, Raymond J; Bestmann, Sven

    2016-03-29

    The effects of stress are frequently studied, yet its proximal causes remain unclear. Here we demonstrate that subjective estimates of uncertainty predict the dynamics of subjective and physiological stress responses. Subjects learned a probabilistic mapping between visual stimuli and electric shocks. Salivary cortisol confirmed that our stressor elicited changes in endocrine activity. Using a hierarchical Bayesian learning model, we quantified the relationship between the different forms of subjective task uncertainty and acute stress responses. Subjective stress, pupil diameter and skin conductance all tracked the evolution of irreducible uncertainty. We observed a coupling between emotional and somatic state, with subjective and physiological tuning to uncertainty tightly correlated. Furthermore, the uncertainty tuning of subjective and physiological stress predicted individual task performance, consistent with an adaptive role for stress in learning under uncertain threat. Our finding that stress responses are tuned to environmental uncertainty provides new insight into their generation and likely adaptive function.

  1. Computations of uncertainty mediate acute stress responses in humans

    PubMed Central

    de Berker, Archy O.; Rutledge, Robb B.; Mathys, Christoph; Marshall, Louise; Cross, Gemma F.; Dolan, Raymond J.; Bestmann, Sven

    2016-01-01

    The effects of stress are frequently studied, yet its proximal causes remain unclear. Here we demonstrate that subjective estimates of uncertainty predict the dynamics of subjective and physiological stress responses. Subjects learned a probabilistic mapping between visual stimuli and electric shocks. Salivary cortisol confirmed that our stressor elicited changes in endocrine activity. Using a hierarchical Bayesian learning model, we quantified the relationship between the different forms of subjective task uncertainty and acute stress responses. Subjective stress, pupil diameter and skin conductance all tracked the evolution of irreducible uncertainty. We observed a coupling between emotional and somatic state, with subjective and physiological tuning to uncertainty tightly correlated. Furthermore, the uncertainty tuning of subjective and physiological stress predicted individual task performance, consistent with an adaptive role for stress in learning under uncertain threat. Our finding that stress responses are tuned to environmental uncertainty provides new insight into their generation and likely adaptive function. PMID:27020312

  2. An overview of stress response proteomes in Listeria monocytogenes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Listeria monocytogenes adapts to diverse stress conditions including cold, osmotic, heat, acid, and alkali stresses encountered during food processing and preservation which is a serious food safety threat. In this review, we have presented the major findings on this bacterium’s stress response prot...

  3. 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…

  4. Plant cell organelle proteomics in response to abiotic stress.

    PubMed

    Hossain, Zahed; Nouri, Mohammad-Zaman; Komatsu, Setsuko

    2012-01-01

    Proteomics is one of the finest molecular techniques extensively being used for the study of protein profiling of a given plant species experiencing stressed conditions. Plants respond to a stress by alteration in the pattern of protein expression, either by up-regulating of the existing protein pool or by the synthesizing novel proteins primarily associated with plants antioxidative defense mechanism. Improved protein extraction protocols and advance techniques for identification of novel proteins have been standardized in different plant species at both cellular and whole plant level for better understanding of abiotic stress sensing and intracellular stress signal transduction mechanisms. In contrast, an in-depth proteome study of subcellular organelles could generate much detail information about the intrinsic mechanism of stress response as it correlates the possible relationship between the protein abundance and plant stress tolerance. Although a wealth of reviews devoted to plant proteomics are available, review articles dedicated to plant cell organelle proteins response under abiotic stress are very scanty. In the present review, an attempt has been made to summarize all significant contributions related to abiotic stresses and their impacts on organelle proteomes for better understanding of plants abiotic stress tolerance mechanism at protein level. This review will not only provide new insights into the plants stress response mechanisms, which are necessary for future development of genetically engineered stress tolerant crop plants for the benefit of humankind, but will also highlight the importance of studying changes in protein abundance within the cell organelles in response to abiotic stress.

  5. Extracytoplasmic Stress Responses Induced by Antimicrobial Cationic Polyethylenimines

    PubMed Central

    Lander, Blaine A.; Checchi, Kyle D.; Koplin, Stephen A.; Smith, Virginia F.; Domanski, Tammy L.; Isaac, Daniel D.; Lin, Shirley

    2014-01-01

    The ability of an antimicrobial, cationic polyethylenimine (PEI+) to induce the three known extracytoplasmic stress responses of Escherichia coli was quantified. Exposure of E. coli to PEI+ in solution revealed specific, concentration-dependent induction of the Cpx extracytoplasmic cellular stress response, ~2.0-2.5 fold at 320 μg/mL after 1.5 hours without significant induction of the σE or Bae stress responses. In comparison, exposure of E. coli to a non-antimicrobial polymer, polyethylene oxide (PEO), resulted in no induction of the three stress responses. The antimicrobial small molecule vanillin, a known membrane pore-forming compound, was observed to cause specific, concentration-dependent induction of the σE stress response, ~6-fold at 640 μg/mL after 1.5 hours, without significant induction of the Cpx or Bae stress responses. The different stress response induction profiles of PEI+ and vanillin suggest that although both are antimicrobial compounds, they interact with the bacterial membrane and extracytoplasmic area by unique mechanisms. EPR studies of liposomes containing spin-labeled lipids exposed to PEI+, vanillin, and PEO reveal that PEI+ and PEO increased membrane stability whereas vanillin was found to have no effect. PMID:22797865

  6. Human Responses to Exercise-Heat Stress

    DTIC Science & Technology

    1993-11-01

    rectal temperature is a good index to assess body core heat storage (177.225). Oral ( sublingual ) temperature is widely used clinically, but less...that immunohistochemical analyses of skin biopsies from these subjects showed that VIP innervation was sparse, while calcitonin gene-related peptide ...proposed that release of one or both of the other peptides , CGRP and substance P, may be the mechanism responsible for active cutaneous vasodilation

  7. The stress response system of proteins: Implications for bioreactor scaleup

    NASA Technical Reports Server (NTRS)

    Goochee, Charles F.

    1988-01-01

    Animal cells face a variety of environmental stresses in large scale bioreactors, including periodic variations in shear stress and dissolved oxygen concentration. Diagnostic techniques were developed for identifying the particular sources of environmental stresses for animal cells in a given bioreactor configuration. The mechanisms by which cells cope with such stresses was examined. The individual concentrations and synthesis rates of hundreds of intracellular proteins are affected by the extracellular environment (medium composition, dissolved oxygen concentration, ph, and level of surface shear stress). Techniques are currently being developed for quantifying the synthesis rates and concentrations of the intracellular proteins which are most sensitive to environmental stress. Previous research has demonstrated that a particular set of stress response proteins are synthesized by mammalian cells in response to temperature fluctuations, dissolved oxygen deprivation, and glucose deprivation. Recently, it was demonstrated that exposure of human kidney cells to high shear stress results in expression of a completely distinct set of intracellular proteins.

  8. Phagocytosis as a biomarker for stress responses

    NASA Astrophysics Data System (ADS)

    Huber, K.; Krotz-Fahning, M.; Hock, B.

    2005-08-01

    An in vitro test has been developed for the detection of immunotoxic events. It will be used within the project "TRIPLE LUX" on the International Space Station to investigate the effects of single and combined space flight conditions on mammalian phagocytes. The intensity of the respiratory burst during phagocytosis can be followed by the luminol-based chemiluminescence response after stimulation with zymosan. We adapted this test system for polymorphonuclear leukocytes, purified from sheep blood and stored by cryoconservation. In this report we show the immunostimulating effect of hydrocortisone and the immunosuppressive impact of cadmium as an example for alterations that can be detected by this test.

  9. Morphologic effects of the stress response in fish.

    PubMed

    Harper, Claudia; Wolf, Jeffrey C

    2009-01-01

    Fish and other aquatic animals are subject to a broad variety of stressors because their homeostatic mechanisms are highly dependent on prevailing conditions in their immediate surroundings. Yet few studies have addressed stress as a potential confounding factor for bioassays that use fish as test subjects. Common stressors encountered by captive fish include physical and mental trauma associated with capture, transport, handling, and crowding; malnutrition; variations in water temperature, oxygen, and salinity; and peripheral effects of contaminant exposure or infectious disease. Some stress responses are detectable through gross or microscopic examination of various organs or tissues; as reported in the literature, stress responses are most consistently observed in the gills, liver, skin, and components of the urogenital tract. In addition to presenting examples of various stressors and corresponding morphologic effects, this review highlights certain challenges of evaluating stress in fish: (1) stress is an amorphous term that does not have a consistently applied definition; (2) procedures used to determine or measure stress can be inherently stressful; (3) interactions between stressors and stress responses are highly complex; and (4) morphologically, stress responses are often difficult to distinguish from tissue damage or compensatory adaptations induced specifically by the stressor. Further investigations are necessary to more precisely define the role of stress in the interpretation of fish research results.

  10. Stress Response and Perinatal Reprogramming: Unraveling (Mal)adaptive Strategies

    PubMed Central

    Musazzi, Laura; Marrocco, Jordan

    2016-01-01

    Environmental stressors induce coping strategies in the majority of individuals. The stress response, involving the activation of the hypothalamic-pituitary-adrenocortical axis and the consequent release of corticosteroid hormones, is indeed aimed at promoting metabolic, functional, and behavioral adaptations. However, behavioral stress is also associated with fast and long-lasting neurochemical, structural, and behavioral changes, leading to long-term remodeling of glutamate transmission, and increased susceptibility to neuropsychiatric disorders. Of note, early-life events, both in utero and during the early postnatal life, trigger reprogramming of the stress response, which is often associated with loss of stress resilience and ensuing neurobehavioral (mal)adaptations. Indeed, adverse experiences in early life are known to induce long-term stress-related neuropsychiatric disorders in vulnerable individuals. Here, we discuss recent findings about stress remodeling of excitatory neurotransmission and brain morphology in animal models of behavioral stress. These changes are likely driven by epigenetic factors that lie at the core of the stress-response reprogramming in individuals with a history of perinatal stress. We propose that reprogramming mechanisms may underlie the reorganization of excitatory neurotransmission in the short- and long-term response to stressful stimuli. PMID:27057367

  11. Stress response dysregulation and stress-induced analgesia in nicotine dependent men and women.

    PubMed

    al'Absi, Mustafa; Nakajima, Motohiro; Grabowski, John

    2013-04-01

    Alterations in the stress response and endogenous pain regulation mechanisms may contribute directly and indirectly to maintenance of nicotine dependence and relapse. We examined the extent to which nicotine dependence alters endogenous pain regulatory systems, including the hypothalamic-pituitary-adrenocortical axis, cardiovascular activity, and stress-induced analgesia. Smokers and nonsmokers attended a laboratory session that included assessment of hormonal and cardiovascular responses to stress. Smokers smoked at their regular rate prior to the session. The hand cold pressor and heat thermal pain tests were completed twice, once after acute stress (public speaking and math tasks) and the other after rest. While smokers and nonsmokers exhibited significant hormonal and cardiovascular responses to stress, smokers exhibited blunted stress responses relative to nonsmokers. They also exhibited diminished stress-induced analgesia. Results demonstrate altered stress response and diminished stress-induced analgesia among chronic smokers, and suggest that these dysregulated physiological responding may contribute to altered endogenous pain regulation.

  12. Nitric oxide signaling in plant responses to abiotic stresses.

    PubMed

    Qiao, Weihua; Fan, Liu-Min

    2008-10-01

    Nitric oxide (NO) plays important roles in diverse physiological processes in plants. NO can provoke both beneficial and harmful effects, which depend on the concentration and location of NO in plant cells. This review is focused on NO synthesis and the functions of NO in plant responses to abiotic environmental stresses. Abiotic stresses mostly induce NO production in plants. NO alleviates the harmfulness of reactive oxygen species, and reacts with other target molecules, and regulates the expression of stress responsive genes under various stress conditions.

  13. Oxidative stress, radiation-adaptive responses, and aging.

    PubMed

    Miura, Yuri

    2004-09-01

    Organisms living in an aerobic environment were forced to evolve effective cellular strategies to detoxify reactive oxygen species. Besides diverse antioxidant enzymes and compounds, DNA repair enzymes, and disassembly systems, which remove damaged proteins, regulation systems that control transcription, translation, and activation have also been developed. The adaptive responses, especially those to radiation, are defensive regulation mechanisms by which oxidative stress (conditioning irradiation) elicits a response against damage because of subsequent stress (challenging irradiation). Although many researchers have investigated these molecular mechanisms, they remain obscure because of their complex signaling pathways and the involvement of various proteins. This article reviews the factors concerned with radiation-adaptive response, the signaling pathways activated by conditioning irradiation, and the effects of aging on radiation-adaptive response. The proteomics approach is also introduced, which is a useful method for studying stress response in cells.

  14. Proteomic responses of fruits to environmental stresses

    PubMed Central

    Chan, Zhulong

    2012-01-01

    Fruits and vegetables are extremely susceptible to decay and easily lose commercial value after harvest. Different strategies have been developed to control postharvest decay and prevent quality deterioration during postharvest storage, including cold storage, controlled atmosphere (CA), and application of biotic and abiotic stimulus. In this review, mechanisms related to protein level responses of host side and pathogen side were characterized. Protein extraction protocols have been successfully developed for recalcitrant, low protein content fruit tissues. Comparative proteome profiling and functional analysis revealed that defense related proteins, energy metabolism, and antioxidant pathway played important roles in fruits in response to storage conditions and exogenous elicitor treatments. Secretome of pathogenic fungi has been well-investigated and the results indicated that hydrolytic enzymes were the key virulent factors for the pathogen infection. These protein level changes shed new light on interaction among fruits, pathogens, and environmental conditions. Potential postharvest strategies to reduce risk of fruit decay were further proposed based on currently available proteomic data. PMID:23335934

  15. Association between neuroticism and amygdala responsivity emerges under stressful conditions.

    PubMed

    Everaerd, Daphne; Klumpers, Floris; van Wingen, Guido; Tendolkar, Indira; Fernández, Guillén

    2015-05-15

    Increased amygdala reactivity in response to salient stimuli is seen in patients with affective disorders, in healthy subjects at risk for these disorders, and in stressed individuals, making it a prime target for mechanistic studies into the pathophysiology of affective disorders. However, whereas individual differences in neuroticism are thought to modulate the effect of stress on mental health, the mechanistic link between stress, neuroticism and amygdala responsivity is unknown. Thus, we studied the relationship between experimentally induced stress, individual differences in neuroticism, and amygdala responsivity. To this end, fearful and happy faces were presented to a large cohort of young, healthy males (n=120) in two separate functional MRI sessions (stress versus control) in a randomized, controlled cross-over design. We revealed that amygdala reactivity was modulated by an interaction between the factors of stress, neuroticism, and the emotional valence of the facial stimuli. Follow-up analysis showed that neuroticism selectively enhanced amygdala responses to fearful faces in the stress condition. Thus, we show that stress unmasks an association between neuroticism and amygdala responsivity to potentially threatening stimuli. This effect constitutes a possible mechanistic link within the complex pathophysiology of affective disorders, and our novel approach appears suitable for further studies targeting the underlying mechanisms.

  16. Stress responses during ageing: molecular pathways regulating protein homeostasis.

    PubMed

    Kyriakakis, Emmanouil; Princz, Andrea; Tavernarakis, Nektarios

    2015-01-01

    The ageing process is characterized by deterioration of physiological function accompanied by frailty and ageing-associated diseases. The most broadly and well-studied pathways influencing ageing are the insulin/insulin-like growth factor 1 signaling pathway and the dietary restriction pathway. Recent studies in diverse organisms have also delineated emerging pathways, which collectively or independently contribute to ageing. Among them the proteostatic-stress-response networks, inextricably affect normal ageing by maintaining or restoring protein homeostasis to preserve proper cellular and organismal function. In this chapter, we survey the involvement of heat stress and endoplasmic reticulum stress responses in the regulation of longevity, placing emphasis on the cross talk between different response mechanisms and their systemic effects. We further discuss novel insights relevant to the molecular pathways mediating these stress responses that may facilitate the development of innovative interventions targeting age-related pathologies such as diabetes, cancer, cardiovascular and neurodegenerative diseases.

  17. Origins of asymmetric stress-strain response in phase transformations

    SciTech Connect

    Sehitoglu, H.; Gall, K.

    1997-12-31

    It has been determined that the transformation stress-strain behavior of CuZnAl and NiTi shape memory alloys is dependent on the applied stress state. The uniaxial compressive stress necessary to macroscopically trigger the transformation is approximately 34% (CuZnAl) and 26% (NiTi) larger than the required uniaxial tensile stress. For three dimensional stress states, the response of either alloy system is dependent on the directions of the dominant principal stresses along with the hydrostatic stress component of the stress state. The stress state effects are dominated by the favored growth and nucleation of more martensite plates in tension versus compression. The effect of different hydrostatic pressure levels between stress states on martensite plates volume change is considered small.

  18. Crop and medicinal plants proteomics in response to salt stress

    PubMed Central

    Aghaei, Keyvan; Komatsu, Setsuko

    2013-01-01

    Increasing of world population marks a serious need to create new crop cultivars and medicinal plants with high growth and production at any environmental situations. Among the environmental unfavorable conditions, salinity is the most widespread in the world. Crop production and growth severely decreases under salt stress; however, some crop cultivars show significant tolerance against the negative effects of salinity. Among salt stress responses of crops, proteomic responses play a pivotal role in their ability to cope with it and have become the main center of notification. Many physiological responses are detectable in terms of protein increase and decrease even before physiological responses take place. Thus proteomic approach makes a short cut in the way of inferring how crops response to salt stress. Nowadays many salt-responsive proteins such as heat shock proteins, pathogen-related proteins, protein kinases, ascorbate peroxidase, osmotin, ornithine decarboxylase, and some transcription factors, have been detected in some major crops which are thought to give them the ability of withstanding against salt stress. Proteomic analysis of medicinal plants also revealed that alkaloid biosynthesis related proteins such as tryptophan synthase, codeinone reductase, strictosidine synthase, and 12-oxophytodienoate reductase might have major role in production of secondary metabolites. In this review we are comparing some different or similar proteomic responses of several crops and medicinal plants to salt stress and discuss about the future prospects. PMID:23386857

  19. Disrupted glucocorticoid--Immune interactions during stress response in schizophrenia.

    PubMed

    Chiappelli, Joshua; Shi, Qiaoyun; Kodi, Priyadurga; Savransky, Anya; Kochunov, Peter; Rowland, Laura M; Nugent, Katie L; Hong, L Elliot

    2016-01-01

    Glucocorticoid and immune pathways typically interact dynamically to optimize adaptation to stressful environmental challenges. We tested the hypothesis that a dysfunctional glucocorticoid-immune relationship contributes to abnormal stress response in schizophrenia. Saliva samples from 34 individuals with schizophrenia (20 male, 14 female) and 40 healthy controls (20 male, 20 female) were collected prior to and at 3 time points following completion of a computerized psychological challenge meant to be frustrating. Salivary concentrations of cortisol and interleukin-6 (IL-6) and their response to the challenge were examined. Both cortisol and IL-6 significantly increased in response to stress in the combined sample (both p<.05). In controls, the rise in cortisol following the challenge was negatively correlated to the subsequent changes in IL-6 (r=-.461, p=.003), such that rise of cortisol immediately after stress predicts subsequently lower IL-6 levels. In contrast, this relationship was positive in schizophrenia patients (r=.379, p=.027). The trends were significantly different (Z=3.7, p=.0002). This stress paradigm induces a rise in both cortisol and IL-6. In healthy controls, a more robust acute cortisol response was associated with a steeper decline of IL-6 levels following stress, corresponding to the expected anti-inflammatory effects of cortisol. Patients exhibited the opposite relationship, suggesting an inability to down-regulate inflammatory responses to psychological stress in schizophrenia; or even a paradoxical increase of IL-6 response. This finding may partially underlie abnormalities in inflammatory and stress pathways previously found in the illness, implicating dysregulated stress response in the chronic inflammatory state in schizophrenia.

  20. 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.

  1. Prenatal cortisol exposure predicts infant cortisol response to acute stress.

    PubMed

    O'Connor, Thomas G; Bergman, Kristin; Sarkar, Pampa; Glover, Vivette

    2013-03-01

    Experimental animal findings suggest that early stress and glucocorticoid exposure may program the function of the hypothalamic-pituitary-adrenal (HPA) axis in the offspring. The extension of these findings to human development is not yet clear. A prospective longitudinal study was conducted on 125 mothers and their normally developing children. Amniotic fluid was obtained at, on average, 17.2 weeks gestation; infant behavior and cortisol response to a separation-reunion stress was assessed at 17 months. Amniotic fluid cortisol predicted infant cortisol response to separation-reunion stress: infants who were exposed to higher levels of cortisol in utero showed higher pre-stress cortisol values and blunted response to stress exposure. The association was independent of prenatal, obstetric, and socioeconomic factors and child-parent attachment. The findings provide some of the strongest data in humans that HPA axis functioning in the child may be predicted from prenatal cortisol exposure.

  2. Formaldehyde Stress Responses in Bacterial Pathogens

    PubMed Central

    Chen, Nathan H.; Djoko, Karrera Y.; Veyrier, Frédéric J.; McEwan, Alastair G.

    2016-01-01

    Formaldehyde is the simplest of all aldehydes and is highly cytotoxic. Its use and associated dangers from environmental exposure have been well documented. Detoxification systems for formaldehyde are found throughout the biological world and they are especially important in methylotrophic bacteria, which generate this compound as part of their metabolism of methanol. Formaldehyde metabolizing systems can be divided into those dependent upon pterin cofactors, sugar phosphates and those dependent upon glutathione. The more prevalent thiol-dependent formaldehyde detoxification system is found in many bacterial pathogens, almost all of which do not metabolize methane or methanol. This review describes the endogenous and exogenous sources of formaldehyde, its toxic effects and mechanisms of detoxification. The methods of formaldehyde sensing are also described with a focus on the formaldehyde responsive transcription factors HxlR, FrmR, and NmlR. Finally, the physiological relevance of detoxification systems for formaldehyde in bacterial pathogens is discussed. PMID:26973631

  3. 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

  4. 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.

  5. The Plant Heat Stress Transcription Factors (HSFs): Structure, Regulation, and Function in Response to Abiotic Stresses.

    PubMed

    Guo, Meng; Liu, Jin-Hong; Ma, Xiao; Luo, De-Xu; Gong, Zhen-Hui; Lu, Ming-Hui

    2016-01-01

    Abiotic stresses such as high temperature, salinity, and drought adversely affect the survival, growth, and reproduction of plants. Plants respond to such unfavorable changes through developmental, physiological, and biochemical ways, and these responses require expression of stress-responsive genes, which are regulated by a network of transcription factors (TFs), including heat stress transcription factors (HSFs). HSFs play a crucial role in plants response to several abiotic stresses by regulating the expression of stress-responsive genes, such as heat shock proteins (Hsps). In this review, we describe the conserved structure of plant HSFs, the identification of HSF gene families from various plant species, their expression profiling under abiotic stress conditions, regulation at different levels and function in abiotic stresses. Despite plant HSFs share highly conserved structure, their remarkable diversification across plants reflects their numerous functions as well as their integration into the complex stress signaling and response networks, which can be employed in crop improvement strategies via biotechnological intervention.

  6. The Plant Heat Stress Transcription Factors (HSFs): Structure, Regulation, and Function in Response to Abiotic Stresses

    PubMed Central

    Guo, Meng; Liu, Jin-Hong; Ma, Xiao; Luo, De-Xu; Gong, Zhen-Hui; Lu, Ming-Hui

    2016-01-01

    Abiotic stresses such as high temperature, salinity, and drought adversely affect the survival, growth, and reproduction of plants. Plants respond to such unfavorable changes through developmental, physiological, and biochemical ways, and these responses require expression of stress-responsive genes, which are regulated by a network of transcription factors (TFs), including heat stress transcription factors (HSFs). HSFs play a crucial role in plants response to several abiotic stresses by regulating the expression of stress-responsive genes, such as heat shock proteins (Hsps). In this review, we describe the conserved structure of plant HSFs, the identification of HSF gene families from various plant species, their expression profiling under abiotic stress conditions, regulation at different levels and function in abiotic stresses. Despite plant HSFs share highly conserved structure, their remarkable diversification across plants reflects their numerous functions as well as their integration into the complex stress signaling and response networks, which can be employed in crop improvement strategies via biotechnological intervention. PMID:26904076

  7. Oxidative stress responses in Escherichia coli and Salmonella typhimurium.

    PubMed Central

    Farr, S B; Kogoma, T

    1991-01-01

    Oxidative stress is strongly implicated in a number of diseases, such as rheumatoid arthritis, inflammatory bowel disorders, and atherosclerosis, and its emerging as one of the most important causative agents of mutagenesis, tumorigenesis, and aging. Recent progress on the genetics and molecular biology of the cellular responses to oxidative stress, primarily in Escherichia coli and Salmonella typhimurium, is summarized. Bacteria respond to oxidative stress by invoking two distinct stress responses, the peroxide stimulon and the superoxide stimulon, depending on whether the stress is mediated by peroxides or the superoxide anion. The two stimulons each contain a set of more than 30 genes. The expression of a subset of genes in each stimulon is under the control of a positive regulatory element; these genes constitute the OxyR and SoxRS regulons. The schemes of regulation of the two regulons by their respective regulators are reviewed in detail, and the overlaps of these regulons with other stress responses such as the heat shock and SOS responses are discussed. The products of Oxy-R- and SoxRS-regulated genes, such as catalases and superoxide dismutases, are involved in the prevention of oxidative damage, whereas others, such as endonuclease IV, play a role in the repair of oxidative damage. The potential roles of these and other gene products in the defense against oxidative damage in DNA, proteins, and membranes are discussed in detail. A brief discussion of the similarities and differences between oxidative stress responses in bacteria and eukaryotic organisms concludes this review. PMID:1779927

  8. Effect of prenatal stress on subsequent response to mixing stress and a lipopolysaccharide challenge in pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sows subjected to prenatal stress have been found to produce offspring that alter the manner in which they respond to stress. Our objective was to determine if exposing a sow to stress altered the response of the offspring to lipopolysaccharide (LPS) at 2 mo of age or their response to mixing stres...

  9. 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.

  10. Traumatic Experience in Infancy: How Responses to Stress Affect Development

    ERIC Educational Resources Information Center

    Witten, Molly Romer

    2010-01-01

    Responses to traumatic stress during the earliest years of life can change quickly and can be difficult to identify because of the young child's rapid rate of development. The symptoms of traumatic stress will depend on the child's developmental level and individual coping styles, as well as the quality and nature of the child's most important…

  11. Personality, Stressful Life Events, and Treatment Response in Major Depression

    ERIC Educational Resources Information Center

    Bulmash, Eric; Harkness, Kate L.; Stewart, Jeremy G.; Bagby, R. Michael

    2009-01-01

    The current study examined whether the personality traits of self-criticism or dependency moderated the effect of stressful life events on treatment response. Depressed outpatients (N = 113) were randomized to 16 weeks of cognitive-behavioral therapy, interpersonal psychotherapy, or antidepressant medication (ADM). Stressful life events were…

  12. Cellular Stress Responses Elicited by Engineered Nanomaterials

    EPA Science Inventory

    Engineered nanomaterials are being incorporated continuously into consumer products, resulting in increased human exposures. The study of engineered nanomaterials has focused largely on oxidative stress and inflammation endpoints without further investigation of underlying pathwa...

  13. Stretching the Stress Boundary: Linking Air Pollution Health Effects to a Neurohormonal Stress Response

    EPA Science Inventory

    Inhaled pollutants produce effects in virtually all organ systems in our body and have been linked to chronic diseases including hypertension, atherosclerosis, Alzheimer’s and diabetes. A neurohormonal stress response (referred here as a systemic response produced by activ...

  14. Stress Responses in Alfalfa (Medicago sativa L.)

    PubMed Central

    Gowri, Ganesan; Bugos, Robert C.; Campbell, Wilbur H.; Maxwell, Carl A.; Dixon, Richard A.

    1991-01-01

    S-Adenosyl-l-methionine:caffeic acid 3-O-methyltransferase (COMT, EC 2.1.1.6) catalyzes the conversion of caffeic acid to ferulic acid, a key step in the biosynthesis of lignin monomers. We have isolated a functionally active cDNA clone (pCOMT1) encoding alfalfa (Medicago sativa L.) COMT by immunoscreening a λZAPII cDNA expression library with anti-(aspen COMT) antibodies. The derived amino acid sequence of pCOMT1 is 86% identical to that of COMT from aspen. Southern blot analysis indicates that COMT in alfalfa is encoded by at least two genes. Addition of an elicitor preparation from bakers' yeast to alfalfa cell suspension cultures resulted in a rapid accumulation of COMT transcripts, which reached a maximum level around 19 hours postelicitation. Northern blot analysis of total RNA from different organs of alfalfa plants at various developmental stages showed that COMT transcripts are most abundant in roots and stems. Transcripts encoding ATP: i-methionine-S-adenosyl transferase (AdoMet synthetase, EC 2.5.1.6), the enzyme responsible for the synthesis of the methyl donor for the COMT reaction, were coinduced with COMT transcripts in elicitor-treated cells and exhibited a similar pattern of expression to that of COMT in different organs of alfalfa plants at various stages of development. ImagesFigure 3Figure 4Figure 6 PMID:16668418

  15. Global Metabolic Responses to Salt Stress in Fifteen Species

    PubMed Central

    Pollak, Georg R.; Kuehne, Andreas; Sauer, Uwe

    2016-01-01

    Cells constantly adapt to unpredictably changing extracellular solute concentrations. A cornerstone of the cellular osmotic stress response is the metabolic supply of energy and building blocks to mount appropriate defenses. Yet, the extent to which osmotic stress impinges on the metabolic network remains largely unknown. Moreover, it is mostly unclear which, if any, of the metabolic responses to osmotic stress are conserved among diverse organisms or confined to particular groups of species. Here we investigate the global metabolic responses of twelve bacteria, two yeasts and two human cell lines exposed to sustained hyperosmotic salt stress by measuring semiquantitative levels of hundreds of cellular metabolites using nontargeted metabolomics. Beyond the accumulation of osmoprotectants, we observed significant changes of numerous metabolites in all species. Global metabolic responses were predominantly species-specific, yet individual metabolites were characteristically affected depending on species’ taxonomy, natural habitat, envelope structure or salt tolerance. Exploiting the breadth of our dataset, the correlation of individual metabolite response magnitudes across all species implicated lower glycolysis, tricarboxylic acid cycle, branched-chain amino acid metabolism and heme biosynthesis to be generally important for salt tolerance. Thus, our findings place the global metabolic salt stress response into a phylogenetic context and provide insights into the cellular phenotype associated with salt tolerance. PMID:26848578

  16. Stress Responses from the Endoplasmic Reticulum in Cancer

    PubMed Central

    Kato, Hironori; Nishitoh, Hideki

    2015-01-01

    The endoplasmic reticulum (ER) is a dynamic organelle that is essential for multiple cellular functions. During cellular stress conditions, including nutrient deprivation and dysregulation of protein synthesis, unfolded/misfolded proteins accumulate in the ER lumen, resulting in activation of the unfolded protein response (UPR). The UPR also contributes to the regulation of various intracellular signaling pathways such as calcium signaling and lipid signaling. More recently, the mitochondria-associated ER membrane (MAM), which is a site of close contact between the ER and mitochondria, has been shown to function as a platform for various intracellular stress responses including apoptotic signaling, inflammatory signaling, the autophagic response, and the UPR. Interestingly, in cancer, these signaling pathways from the ER are often dysregulated, contributing to cancer cell metabolism. Thus, the signaling pathway from the ER may be a novel therapeutic target for various cancers. In this review, we discuss recent research on the roles of stress responses from the ER, including the MAM. PMID:25941664

  17. Diazepam and Fluoxetine Decrease the Stress Response in Zebrafish

    PubMed Central

    de Abreu, Murilo Sander; Koakoski, Gessi; Ferreira, Daiane; Oliveira, Thiago Acosta; da Rosa, João Gabriel Santos; Gusso, Darlan; Giacomini, Ana Cristina Varrone; Piato, Angelo Luis; Barcellos, Leonardo José Gil

    2014-01-01

    The presence of pharmaceutical products in the aquatic environment has been reported in several studies. However, the impact of these drugs on living organisms is still uncharacterized. Here, we investigated the effects of acute exposure to either diazepam or fluoxetine on the stress response in Danio rerio. We showed that diazepam and fluoxetine inhibited the stress axis in zebrafish. Intermediate concentrations of diazepam suppressed the stress response as measured by cortisol levels, whereas fluoxetine inhibited cortisol increase at concentrations similar to those found in the environment. These data suggest that the presence of psychoactive drugs in aquatic ecosystems could cause neuroendocrine dysfunction in fish. PMID:25054216

  18. Influence of surface stresses on indentation response.

    PubMed

    Buchwald, J; Mayr, S G

    2015-03-27

    Surface stresses lead to an effective change in the elastic constants of thin films and at surfaces. The development of modern scanning probe techniques like contact resonance atomic force microscopy empowers the experimenter to measure at scales where these effects become increasingly relevant. In this paper we employ a computational multiscale approach where we compare density functional theory (DFT) and molecular dynamics simulations as tools to calculate the thin-film/surface elastic behavior for silicon and strontiumtitanate. From the surface elastic constants gained by DFT calculations we develop a continuum finite-element multilayer model to study the impact of surface stresses on indentation experiments. In general the stress field of an indenter and thus the impact of surface stresses on the indentation modulus depends on its contact radius and on its particular shape. We propose an analytical model that describes the behavior of the indentation modulus as a function of the contact radius. We show that this model fits well to simulation results gained for a spherical and a flat punch indenter. Our results demonstrate a surface-stress-induced reduction of the indentation modulus of about 5% for strontiumtitanate and 6% for silicon for a contact radius of [Formula: see text], irrespective of the indenter shape.

  19. Influence of surface stresses on indentation response

    NASA Astrophysics Data System (ADS)

    Buchwald, J.; Mayr, S. G.

    2015-03-01

    Surface stresses lead to an effective change in the elastic constants of thin films and at surfaces. The development of modern scanning probe techniques like contact resonance atomic force microscopy empowers the experimenter to measure at scales where these effects become increasingly relevant. In this paper we employ a computational multiscale approach where we compare density functional theory (DFT) and molecular dynamics simulations as tools to calculate the thin-film/surface elastic behavior for silicon and strontiumtitanate. From the surface elastic constants gained by DFT calculations we develop a continuum finite-element multilayer model to study the impact of surface stresses on indentation experiments. In general the stress field of an indenter and thus the impact of surface stresses on the indentation modulus depends on its contact radius and on its particular shape. We propose an analytical model that describes the behavior of the indentation modulus as a function of the contact radius. We show that this model fits well to simulation results gained for a spherical and a flat punch indenter. Our results demonstrate a surface-stress-induced reduction of the indentation modulus of about 5% for strontiumtitanate and 6% for silicon for a contact radius of {{r}c}=5 \\text{nm}, irrespective of the indenter shape.

  20. The influence of neuroticism, extraversion and openness on stress responses.

    PubMed

    Schneider, Tamera R; Rench, Tara A; Lyons, Joseph B; Riffle, Rebecca R

    2012-04-01

    The present research moved beyond focusing on negative dispositions to investigate the influence of positive aspects of personality, namely extraversion and openness, on stress responses including appraisals, affect and task performance. Challenge appraisals occur when stressor demands are deemed commensurate with coping resources, whereas threat appraisals occur when demands are believed to outweigh coping resources. We examined the unique influence of personality on stress responses and the mediating role of appraisals. Personality was assessed, and then participants (N = 152) were exposed to a validated math stressor. We found unique effects on stress responses for neuroticism (high threat and negative affect and low positive affect), extraversion (high positive and low negative affect) and openness (high positive and low negative effect and better performance). Mediation analyses revealed that neuroticism indirectly worsened performance, through threat appraisals, and that openness indirectly increased positive affect through lower threat. These findings highlight the importance of investigating multiple aspects of personality on stress responses and provide an avenue through which stress responses can be changed-appraisals. Only by more broad investigations can interventions be tailored appropriately for different individuals to foster stress resilience.

  1. Characterization of the general stress response in Bartonella henselae

    PubMed Central

    Tu, Nhan; Lima, Amorce; Bandeali, Zahra; Anderson, Burt

    2016-01-01

    Bacteria utilize a general stress response system to combat stresses from their surrounding environments. In alpha-proteobacteria, the general stress response uses an alternate sigma factor as the main regulator and incorporates it with a two-component system into a unique regulatory circuit. This system has been described in several alpha-proteobacterial species, including the pathogens Bartonella quintana and Brucella abortus. Most of the studies have focused on characterizing the PhyR anti-anti-sigma factor, the NepR anti-sigma factor, and the alternate sigma factor. However, not enough attention is directed toward studying the role of histidine kinases in the general stress response. Our study identifies the general stress response system in Bartonella henselae, where the gene synteny is conserved and both the PhyR and alternate sigma factor have similar sequence and domain structures with other alpha-proteobacteria. Our data showed that the general stress response genes are up-regulated under conditions that mimic the cat flea vector. Furthermore, we showed that both RpoE and PhyR positively regulate this system and that RpoE also affects transcription of genes encoding heme-binding proteins and the gene encoding the BadA adhesin. Finally, we identified a histidine kinase, annotated as BH13820 that can potentially phosphorylate PhyR. PMID:26724735

  2. Chloroplast Retrograde Regulation of Heat Stress Responses in Plants

    PubMed Central

    Sun, Ai-Zhen; Guo, Fang-Qing

    2016-01-01

    It is well known that intracellular signaling from chloroplast to nucleus plays a vital role in stress responses to survive environmental perturbations. The chloroplasts were proposed as sensors to heat stress since components of the photosynthetic apparatus housed in the chloroplast are the major targets of thermal damage in plants. Thus, communicating subcellular perturbations to the nucleus is critical during exposure to extreme environmental conditions such as heat stress. By coordinating expression of stress specific nuclear genes essential for adaptive responses to hostile environment, plants optimize different cell functions and activate acclimation responses through retrograde signaling pathways. The efficient communication between plastids and the nucleus is highly required for such diverse metabolic and biosynthetic functions during adaptation processes to environmental stresses. In recent years, several putative retrograde signals released from plastids that regulate nuclear genes have been identified and signaling pathways have been proposed. In this review, we provide an update on retrograde signals derived from tetrapyrroles, carotenoids, reactive oxygen species (ROS) and organellar gene expression (OGE) in the context of heat stress responses and address their roles in retrograde regulation of heat-responsive gene expression, systemic acquired acclimation, and cellular coordination in plants. PMID:27066042

  3. Antioxidant responses of wheat plants under stress

    PubMed Central

    Caverzan, Andréia; Casassola, Alice; Brammer, Sandra Patussi

    2016-01-01

    Abstract Currently, food security depends on the increased production of cereals such as wheat (Triticum aestivum L.), which is an important source of calories and protein for humans. However, cells of the crop have suffered from the accumulation of reactive oxygen species (ROS), which can cause severe oxidative damage to the plants, due to environmental stresses. ROS are toxic molecules found in various subcellular compartments. The equilibrium between the production and detoxification of ROS is sustained by enzymatic and nonenzymatic antioxidants. In the present review, we offer a brief summary of antioxidant defense and hydrogen peroxide (H2O2) signaling in wheat plants. Wheat plants increase antioxidant defense mechanisms under abiotic stresses, such as drought, cold, heat, salinity and UV-B radiation, to alleviate oxidative damage. Moreover, H2O2 signaling is an important factor contributing to stress tolerance in cereals. PMID:27007891

  4. 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

  5. Exercise-Induced Oxidative Stress Responses in the Pediatric Population.

    PubMed

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

    2017-01-17

    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.

  6. Qualitative Development of the PROMIS® Pediatric Stress Response Item Banks

    PubMed Central

    Gardner, William; Pajer, Kathleen; Riley, Anne W.; Forrest, Christopher B.

    2013-01-01

    Objective To describe the qualitative development of the Patient-Reported Outcome Measurement Information System (PROMIS®) Pediatric Stress Response item banks. Methods Stress response concepts were specified through a literature review and interviews with content experts, children, and parents. A library comprising 2,677 items derived from 71 instruments was developed. Items were classified into conceptual categories; new items were written and redundant items were removed. Items were then revised based on cognitive interviews (n = 39 children), readability analyses, and translatability reviews. Results 2 pediatric Stress Response sub-domains were identified: somatic experiences (43 items) and psychological experiences (64 items). Final item pools cover the full range of children’s stress experiences. Items are comprehensible among children aged ≥8 years and ready for translation. Conclusions Child- and parent-report versions of the item banks assess children’s somatic and psychological states when demands tax their adaptive capabilities. PMID:23124904

  7. Cell Wall Metabolism in Response to Abiotic Stress.

    PubMed

    Le Gall, Hyacinthe; Philippe, Florian; Domon, Jean-Marc; Gillet, Françoise; Pelloux, Jérôme; Rayon, Catherine

    2015-02-16

    This review focuses on the responses of the plant cell wall to several abiotic stresses including drought, flooding, heat, cold, salt, heavy metals, light, and air pollutants. The effects of stress on cell wall metabolism are discussed at the physiological (morphogenic), transcriptomic, proteomic and biochemical levels. The analysis of a large set of data shows that the plant response is highly complex. The overall effects of most abiotic stress are often dependent on the plant species, the genotype, the age of the plant, the timing of the stress application, and the intensity of this stress. This shows the difficulty of identifying a common pattern of stress response in cell wall architecture that could enable adaptation and/or resistance to abiotic stress. However, in most cases, two main mechanisms can be highlighted: (i) an increased level in xyloglucan endotransglucosylase/hydrolase (XTH) and expansin proteins, associated with an increase in the degree of rhamnogalacturonan I branching that maintains cell wall plasticity and (ii) an increased cell wall thickening by reinforcement of the secondary wall with hemicellulose and lignin deposition. Taken together, these results show the need to undertake large-scale analyses, using multidisciplinary approaches, to unravel the consequences of stress on the cell wall. This will help identify the key components that could be targeted to improve biomass production under stress conditions.

  8. Cell Wall Metabolism in Response to Abiotic Stress

    PubMed Central

    Gall, Hyacinthe Le; Philippe, Florian; Domon, Jean-Marc; Gillet, Françoise; Pelloux, Jérôme; Rayon, Catherine

    2015-01-01

    This review focuses on the responses of the plant cell wall to several abiotic stresses including drought, flooding, heat, cold, salt, heavy metals, light, and air pollutants. The effects of stress on cell wall metabolism are discussed at the physiological (morphogenic), transcriptomic, proteomic and biochemical levels. The analysis of a large set of data shows that the plant response is highly complex. The overall effects of most abiotic stress are often dependent on the plant species, the genotype, the age of the plant, the timing of the stress application, and the intensity of this stress. This shows the difficulty of identifying a common pattern of stress response in cell wall architecture that could enable adaptation and/or resistance to abiotic stress. However, in most cases, two main mechanisms can be highlighted: (i) an increased level in xyloglucan endotransglucosylase/hydrolase (XTH) and expansin proteins, associated with an increase in the degree of rhamnogalacturonan I branching that maintains cell wall plasticity and (ii) an increased cell wall thickening by reinforcement of the secondary wall with hemicellulose and lignin deposition. Taken together, these results show the need to undertake large-scale analyses, using multidisciplinary approaches, to unravel the consequences of stress on the cell wall. This will help identify the key components that could be targeted to improve biomass production under stress conditions. PMID:27135320

  9. Vascular mechanobiology: endothelial cell responses to fluid shear stress.

    PubMed

    Ando, Joji; Yamamoto, Kimiko

    2009-11-01

    Endothelial cells (ECs) lining blood vessel walls respond to shear stress, a fluid mechanical force generated by flowing blood, and the EC responses play an important role in the homeostasis of the circulatory system. Abnormal EC responses to shear stress impair various vascular functions and lead to vascular diseases, including hypertension, thrombosis, and atherosclerosis. Bioengineering approaches in which cultured ECs are subjected to shear stress in fluid-dynamically designed flow-loading devices have been widely used to analyze EC responses at the cellular and molecular levels. Remarkable progress has been made, and the results have shown that ECs alter their morphology, function, and gene expression in response to shear stress. Shear stress affects immature cells, as well as mature ECs, and promotes differentiation of bone-marrow-derived endothelial progenitor cells and embryonic stem cells into ECs. Much research has been done on shear stress sensing and signal transduction, and their molecular mechanisms are gradually coming to be understood. However, much remains uncertain, and many candidates have been proposed for shear stress sensors. More extensive studies of vascular mechanobiology should increase our understanding of the molecular basis of the blood-flow-mediated control of vascular functions.

  10. Seismic stress responses of soybean to different photosynthetic photon flux

    NASA Technical Reports Server (NTRS)

    Jones, R. S.; Coe, L. L.; Montgomery, L.; Mitchell, C. A.

    1990-01-01

    Physical agitation applied as periodic seismic stress (shaking) reduced stem elongation, leaf expansion, and biomass accumulation by vegetative soybeans. Level of photon flux (PPF) influenced the type and extent of plant response to mechanical stress. Plant parts responded differently as PPF varied between 135 and 592 micromoles m-2 s-1. Stem length was significantly reduced by seismic stress at 135 micromoles m-2 s-1 but this effect was insignificant at higher PPFs. Reduced stem length resulted from an inhibition of internode elongation. Stem diameter was unaffected by stress at the PPFs tested. In contrast to effects on stem elongation, leaf area was insensitive to stress treatments at 135 micromoles m-2 s-1 but was progressively inhibited by stress as PPF increased. Statistically significant reductions in shoot f. wt and d. wt by seismic stress occurred only at 295 micromoles m-2 s-1. Root biomass accumulation was not affected by seismic stress at any PPF used in this study.

  11. Detection of early plant stress responses in hyperspectral images

    NASA Astrophysics Data System (ADS)

    Behmann, Jan; Steinrücken, Jörg; Plümer, Lutz

    2014-07-01

    Early stress detection in crop plants is highly relevant, but hard to achieve. We hypothesize that close range hyperspectral imaging is able to uncover stress related processes non-destructively in the early stages which are invisible to the human eye. We propose an approach which combines unsupervised and supervised methods in order to identify several stages of progressive stress development from series of hyperspectral images. Stress of an entire plant is detected by stress response levels at pixel scale. The focus is on drought stress in barley (Hordeum vulgare). Unsupervised learning is used to separate hyperspectral signatures into clusters related to different stages of stress response and progressive senescence. Whereas all such signatures may be found in both, well watered and drought stressed plants, their respective distributions differ. Ordinal classification with Support Vector Machines (SVM) is used to quantify and visualize the distribution of progressive stages of senescence and to separate well watered from drought stressed plants. For each senescence stage a distinctive set of most relevant Vegetation Indices (VIs) is identified. The method has been applied on two experiments involving potted barley plants under well watered and drought stress conditions in a greenhouse. Drought stress is detected up to ten days earlier than using NDVI. Furthermore, it is shown that some VIs have overall relevance, while others are specific to particular senescence stages. The transferability of the method to the field is illustrated by an experiment on maize (Zea mays).

  12. Responses of cariogenic streptococci to environmental stresses.

    PubMed

    Lemos, José A C; Abranches, Jacqueline; Burne, Robert A

    2005-01-01

    To persist in the oral cavity, bacteria must be able to tolerate rapid and substantial environmental fluctuations, particularly in pH and nutrient source and availability. Various species of Streptococcus, one of the most abundant genera in the mouth, are associated with oral health, as well as with dental caries. Cariogenic streptococci depend on a biofilm lifestyle for survival and persistence in the oral cavity and have developed sophisticated mechanisms to cope with environmental stresses. Here, we analyze the primary factors that allow these bacteria to emerge as significant members of tooth biofilms during adverse conditions. Our focus is on the molecular mechanisms of biofilm formation, stress tolerance and sugar metabolism by pathogenic oral streptococci, mainly Streptococcus mutans. Overlaps in the roles and regulation of these virulence attributes are highlighted and areas of research that deserve further investigation are proposed.

  13. miRNA modulation of the cellular stress response.

    PubMed

    Babar, Imran A; Slack, Frank J; Weidhaas, Joanne B

    2008-04-01

    Cellular stress responses are potent and dynamic, allowing cells to effectively counteract diverse stresses. These pathways are crucial not only for maintaining normal cellular homeostasis, but also for protecting cells from what would otherwise lead to their demise. A novel class of genes, termed miRNAs, has recently been implicated in the cellular stress response. For example, it has been demonstrated that a cardiac-specific miRNA that is not required for normal development is requisite for a normal cardiac stress response in mice. In addition, we have found that a miRNA family is able to modulate the cellular response to cytotoxic cancer treatment both in vitro and in vivo. In this review, we will discuss these and other important developments in the field. In particular, we will focus on studies that have linked miRNAs to the genotoxic stress response and will suggest how this connection may be both important for our understanding of biology and pertinent for the development of novel cancer therapies.

  14. Cis-element of the rice PDIL2-3 promoter is responsible for inducing the endoplasmic reticulum stress response.

    PubMed

    Takahashi, Hideyuki; Wang, Shuyi; Hayashi, Shimpei; Wakasa, Yuhya; Takaiwa, Fumio

    2014-05-01

    A protein disulfide isomerase (PDI) family oxidoreductase, PDIL2-3, is involved in endoplasmic reticulum (ER) stress responses in rice. We identified a critical cis-element required for induction of the ER stress response. The activation of PDIL2-3 in response to ER stress strongly depends on the IRE1-OsbZIP50 signaling pathway.

  15. ROS Regulation During Abiotic Stress Responses in Crop Plants.

    PubMed

    You, Jun; Chan, Zhulong

    2015-01-01

    Abiotic stresses such as drought, cold, salt and heat cause reduction of plant growth and loss of crop yield worldwide. Reactive oxygen species (ROS) including hydrogen peroxide (H2O2), superoxide anions (O2 (•-)), hydroxyl radical (OH•) and singlet oxygen ((1)O2) are by-products of physiological metabolisms, and are precisely controlled by enzymatic and non-enzymatic antioxidant defense systems. ROS are significantly accumulated under abiotic stress conditions, which cause oxidative damage and eventually resulting in cell death. Recently, ROS have been also recognized as key players in the complex signaling network of plants stress responses. The involvement of ROS in signal transduction implies that there must be coordinated function of regulation networks to maintain ROS at non-toxic levels in a delicate balancing act between ROS production, involving ROS generating enzymes and the unavoidable production of ROS during basic cellular metabolism, and ROS-scavenging pathways. Increasing evidence showed that ROS play crucial roles in abiotic stress responses of crop plants for the activation of stress-response and defense pathways. More importantly, manipulating ROS levels provides an opportunity to enhance stress tolerances of crop plants under a variety of unfavorable environmental conditions. This review presents an overview of current knowledge about homeostasis regulation of ROS in crop plants. In particular, we summarize the essential proteins that are involved in abiotic stress tolerance of crop plants through ROS regulation. Finally, the challenges toward the improvement of abiotic stress tolerance through ROS regulation in crops are discussed.

  16. Modulation of immune responses in stress by Yoga

    PubMed Central

    Arora, Sarika; Bhattacharjee, Jayashree

    2008-01-01

    Stress is a constant factor in today's fastpaced life that can jeopardize our health if left unchecked. It is only in the last half century that the role of stress in every ailment from the common cold to AIDS has been emphasized, and the mechanisms involved in this process have been studied. Stress influences the immune response presumably through the activation of the hypothalamic-pituitary adrenal axis, hypothalamic pituitary-gonadal axis, and the sympathetic-adrenal-medullary system. Various neurotransmitters, neuropeptides, hormones, and cytokines mediate these complex bidirectional interactions between the central nervous system (CNS) and the immune system. The effects of stress on the immune responses result in alterations in the number of immune cells and cytokine dysregulation. Various stress management strategies such as meditation, yoga, hypnosis, and muscle relaxation have been shown to reduce the psychological and physiological effects of stress in cancers and HIV infection. This review aims to discuss the effect of stress on the immune system and examine how relaxation techniques such as Yoga and meditation could regulate the cytokine levels and hence, the immune responses during stress. PMID:21829284

  17. ROS Regulation During Abiotic Stress Responses in Crop Plants

    PubMed Central

    You, Jun; Chan, Zhulong

    2015-01-01

    Abiotic stresses such as drought, cold, salt and heat cause reduction of plant growth and loss of crop yield worldwide. Reactive oxygen species (ROS) including hydrogen peroxide (H2O2), superoxide anions (O2•-), hydroxyl radical (OH•) and singlet oxygen (1O2) are by-products of physiological metabolisms, and are precisely controlled by enzymatic and non-enzymatic antioxidant defense systems. ROS are significantly accumulated under abiotic stress conditions, which cause oxidative damage and eventually resulting in cell death. Recently, ROS have been also recognized as key players in the complex signaling network of plants stress responses. The involvement of ROS in signal transduction implies that there must be coordinated function of regulation networks to maintain ROS at non-toxic levels in a delicate balancing act between ROS production, involving ROS generating enzymes and the unavoidable production of ROS during basic cellular metabolism, and ROS-scavenging pathways. Increasing evidence showed that ROS play crucial roles in abiotic stress responses of crop plants for the activation of stress-response and defense pathways. More importantly, manipulating ROS levels provides an opportunity to enhance stress tolerances of crop plants under a variety of unfavorable environmental conditions. This review presents an overview of current knowledge about homeostasis regulation of ROS in crop plants. In particular, we summarize the essential proteins that are involved in abiotic stress tolerance of crop plants through ROS regulation. Finally, the challenges toward the improvement of abiotic stress tolerance through ROS regulation in crops are discussed. PMID:26697045

  18. Endocrine stress responses and risk of type 2 diabetes mellitus.

    PubMed

    Siddiqui, Azaz; Madhu, S V; Sharma, S B; Desai, N G

    2015-08-13

    This study was carried to ascertain whether stress responses are associated with abnormalities in glucose tolerance, insulin sensitivity and pancreatic beta cell function and risk of type 2 Diabetes Mellitus. Salivary cortisol, a marker of hypothalamic-pituitary-adrenal (HPA) axis and salivary α-amylase, a marker of sympathetic nervous system (SNS) were compared in 125 subjects of newly detected diabetes mellitus (NDDM) and normal glucose tolerance (NGT) subjects who were diagnosed on the basis of oral glucose tolerance test (OGTT). Assessment of stress in them was done through stress scales - presumptive stressful life events scale (PSLES), perceived stress scale (PSS) and sense of coherence (SOC) and correlated with these and other stress response markers. Significantly higher 10 pm salivary cortisol and post dexamethasone salivary cortisol were found in NDDM subjects as compared to NGT. 10 pm salivary cortisol correlated significantly with fasting plasma glucose (FPG), 2 h plasma glucose (2h PG) and glycated hemoglobin (HbA1c) while post dex salivary cortisol correlated with 2h PG, HbA1c and salivary α-amylase with 2h PG. Stepwise logistic regression analysis showed that body mass index (OR: 1.840), SOC (OR: 0.688) and 10 pm salivary cortisol (OR: 1.427) were the strongest predictors of NDDM. The results of the present study indicate that NDDM subjects display significantly higher chronic stress and stress responses when compared to subjects with NGT. Chronic stress and endocrine stress responses are significantly associated with glucose intolerance, insulin resistance and diabetes mellitus.

  19. Endocrine stress responses and risk of type 2 diabetes mellitus.

    PubMed

    Siddiqui, Azaz; Madhu, S V; Sharma, S B; Desai, N G

    2015-01-01

    This study was carried to ascertain whether stress responses are associated with abnormalities in glucose tolerance, insulin sensitivity and pancreatic beta cell function and risk of type 2 Diabetes Mellitus. Salivary cortisol, a marker of hypothalamic-pituitary-adrenal (HPA) axis and salivary α-amylase, a marker of sympathetic nervous system (SNS) were compared in 125 subjects of newly detected diabetes mellitus (NDDM) and normal glucose tolerance (NGT) subjects who were diagnosed on the basis of oral glucose tolerance test (OGTT). Assessment of stress in them was done through stress scales - presumptive stressful life events scale (PSLES), perceived stress scale (PSS) and sense of coherence (SOC) and correlated with these and other stress response markers. Significantly higher 10 pm salivary cortisol and post dexamethasone salivary cortisol were found in NDDM subjects as compared to NGT. 10 pm salivary cortisol correlated significantly with fasting plasma glucose (FPG), 2 h plasma glucose (2h PG) and glycated hemoglobin (HbA1c) while post dex salivary cortisol correlated with 2h PG, HbA1c and salivary α-amylase with 2h PG. Stepwise logistic regression analysis showed that body mass index (OR: 1.840), SOC (OR: 0.688) and 10 pm salivary cortisol (OR: 1.427) were the strongest predictors of NDDM. The results of the present study indicate that NDDM subjects display significantly higher chronic stress and stress responses when compared to subjects with NGT. Chronic stress and endocrine stress responses are significantly associated with glucose intolerance, insulin resistance and diabetes mellitus.

  20. Seasonal variation in the degu (Octodon degus) endocrine stress response.

    PubMed

    Bauer, Carolyn M; Hayes, Loren D; Ebensperger, Luis A; Romero, L Michael

    2014-02-01

    Many wild animals show seasonal variation in circulating levels of stress hormones. Seasonal changes in the stress response may help animals better cope with the different challenges faced during each life history stage. We determined the seasonal stress profile of wild, free-living degus in Chile. Female degus were sampled during non-breeding (January), mating/early gestation (July), late gestation (August), and lactation (1st litter-September, 2nd litter-January). Male degus were sampled during the first three time-points. We measured baseline cortisol (CORT), stress-induced CORT, and negative feedback efficacy using a dexamethasone suppression test. While we found that neither males nor females showed seasonal variation in baseline CORT or negative feedback levels, we did find significant seasonal variation in stress-induced CORT levels of both sexes. Male stress-induced CORT was lowest during mating while female stress-induced CORT was highest during late gestation and lactation. Overall, females had higher stress-induced CORT compared to males. Our data suggest that stress-induced levels of CORT are highest during periods with increased chance of stressor exposure or times of positive energy balance. Consequently, CORT responses to stress appear to be regulated according to different life history needs.

  1. Keratins Are Altered in Intestinal Disease-Related Stress Responses

    PubMed Central

    Helenius, Terhi O.; Antman, Cecilia A.; Asghar, Muhammad Nadeem; Nyström, Joel H.; Toivola, Diana M.

    2016-01-01

    Keratin (K) intermediate filaments can be divided into type I/type II proteins, which form obligate heteropolymers. Epithelial cells express type I-type II keratin pairs, and K7, K8 (type II) and K18, K19 and K20 (type I) are the primary keratins found in the single-layered intestinal epithelium. Keratins are upregulated during stress in liver, pancreas, lung, kidney and skin, however, little is known about their dynamics in the intestinal stress response. Here, keratin mRNA, protein and phosphorylation levels were studied in response to murine colonic stresses modeling human conditions, and in colorectal cancer HT29 cells. Dextran sulphate sodium (DSS)-colitis was used as a model for intestinal inflammatory stress, which elicited a strong upregulation and widened crypt distribution of K7 and K20. K8 levels were slightly downregulated in acute DSS, while stress-responsive K8 serine-74 phosphorylation (K8 pS74) was increased. By eliminating colonic microflora using antibiotics, K8 pS74 in proliferating cells was significantly increased, together with an upregulation of K8 and K19. In the aging mouse colon, most colonic keratins were upregulated. In vitro, K8, K19 and K8 pS74 levels were increased in response to lipopolysaccharide (LPS)-induced inflammation in HT29 cells. In conclusion, intestinal keratins are differentially and dynamically upregulated and post-translationally modified during stress and recovery. PMID:27626448

  2. Cellular stress response pathways and ageing: intricate molecular relationships.

    PubMed

    Kourtis, Nikos; Tavernarakis, Nektarios

    2011-05-17

    Ageing is driven by the inexorable and stochastic accumulation of damage in biomolecules vital for proper cellular function. Although this process is fundamentally haphazard and uncontrollable, senescent decline and ageing is broadly influenced by genetic and extrinsic factors. Numerous gene mutations and treatments have been shown to extend the lifespan of diverse organisms ranging from the unicellular Saccharomyces cerevisiae to primates. It is becoming increasingly apparent that most such interventions ultimately interface with cellular stress response mechanisms, suggesting that longevity is intimately related to the ability of the organism to effectively cope with both intrinsic and extrinsic stress. Here, we survey the molecular mechanisms that link ageing to main stress response pathways, and mediate age-related changes in the effectiveness of the response to stress. We also discuss how each pathway contributes to modulate the ageing process. A better understanding of the dynamics and reciprocal interplay between stress responses and ageing is critical for the development of novel therapeutic strategies that exploit endogenous stress combat pathways against age-associated pathologies.

  3. Effects of d-amphetamine upon psychosocial stress responses.

    PubMed

    Childs, Emma; Bershad, Anya K; de Wit, Harriet

    2016-07-01

    Psychostimulant drugs alter the salience of stimuli in both laboratory animals and humans. In animals, stimulants increase rates of responding to conditioned incentive stimuli, and in humans, amphetamine increases positive ratings of emotional images. However, the effects of stimulants on real-life emotional events have not been studied in humans. In this study, we examined the effect of d-amphetamine on responses to acute psychosocial stress using a public speaking task. Healthy volunteers (N=56) participated in two experimental sessions, one with a psychosocial stressor (the Trier Social Stress Test) and one with a non-stressful control task. They were randomly assigned to receive d-amphetamine (5 mg n=18, 10 mg n=20) or placebo (n=18) on both sessions under double blind conditions. Salivary cortisol, subjective mood, and vital signs were measured at regular intervals during the session. Subjects also provided cognitive appraisals of the tasks before and after their performances. Amphetamine produced its expected mood and physiological effects, and the Trier Social Stress Test produced its expected effects on cortisol and mood. Although neither dose of amphetamine altered cardiovascular or hormonal responses to stress, amphetamine (10 mg) increased participants' pre-task appraisals of how challenging the task would be, and it increased post-task ratings of self-efficacy. Paradoxically, it also increased ratings of how stressful the task was, and prolonged aversive emotional responses. These findings suggest that amphetamine differentially affects stress response components: it may increase participants' appraisals of self-efficacy without dampening the direct emotional or physiological responses to the stress.

  4. Recent Molecular Advances on Downstream Plant Responses to Abiotic Stress

    PubMed Central

    dos Reis, Sávio Pinho; Lima, Aline Medeiros; de Souza, Cláudia Regina Batista

    2012-01-01

    Abiotic stresses such as extremes of temperature and pH, high salinity and drought, comprise some of the major factors causing extensive losses to crop production worldwide. Understanding how plants respond and adapt at cellular and molecular levels to continuous environmental changes is a pre-requisite for the generation of resistant or tolerant plants to abiotic stresses. In this review we aimed to present the recent advances on mechanisms of downstream plant responses to abiotic stresses and the use of stress-related genes in the development of genetically engineered crops. PMID:22942725

  5. The Stress Response of Escherichia coli under Microgravity.

    NASA Astrophysics Data System (ADS)

    Lynch, S.; Matin, A.

    At the onset of adverse environmental conditions, bacteria induce a controlled stress response to enable survival. Escherichia coli induces stress-specific reactions in response to a variety of environmental strains. A family of proteins termed sigma (s) factors is pivotal to the regulation of stress responses in bacteria. In particular Sigma S (ss) regulates several stress responses in E. coli and serves as an important global stress regulatory protein. Under optimal growth conditions, levels of ss are maintained at low cellular concentrations primarily via a proteolytic regulatory mechanism. At the onset of stress, ss levels increase due to increased stability of the molecule, facilitating transcriptional initiation and up regulation of specific stress related proteins. Concentrations of ss can therefore be indicative of cellular stress levels. Recent work by Kendrick et al demonstrated that Salmonella species grown under conditions of simulated microgravity display increased virulence - a stress-related phenotype. Using E. coli as a model system we aim to investigate the stress response elicited by the organism under conditions of simulated microgravity (SMG). SMG is generated in specially constructed rotary cell culture systems termed HARVs (High Aspect Ratio Vessels- Synthecon Inc.). By rotating at constant velocity around a vertical axis an environment is produced in which the gravitational vectors are randomized over the surface of the cell, resulting in an overall-time-averaged gravitational vector of 10-2 x g (4). E. coli cultures grown in HARVs under conditions of normal gravity (NG) and SMG repeatedly display slower growth kinetics under SMG. Western analysis of cells at exponential and stationary phase of growth from both cultures reveal similar levels of ss exist in exponential phase under both SMG and NG conditions. However, during stationary phase, levels of ss are at least 2-fold higher under conditions of SMG as compared to NG. Translational fusion

  6. Adaptive Patterns of Stress Responsivity: A Preliminary Investigation

    PubMed Central

    Del Giudice, Marco; Hinnant, J. Benjamin; Ellis, Bruce J.; El-Sheikh, Mona

    2014-01-01

    The adaptive calibration model (ACM) is an evolutionary–developmental theory of individual differences in stress responsivity. In this article, we tested some key predictions of the ACM in a middle childhood sample (N = 256). Measures of autonomic nervous system activity across the sympathetic and parasympathetic branches validated the 4-pattern taxonomy of the ACM via finite mixture modeling. Moreover, the 4 patterns of responsivity showed the predicted associations with family stress levels but no association with measures of ecological stress. Our hypotheses concerning sex differences in responsivity were only partly confirmed. This preliminary study provides initial support for the key predictions of the ACM and highlights some of the methodological challenges that will need to be considered in future research on this topic. PMID:22148947

  7. Lipid Biosynthesis Coordinates a Mitochondrial-to-Cytosolic Stress Response.

    PubMed

    Kim, Hyun-Eui; Grant, Ana Rodrigues; Simic, Milos S; Kohnz, Rebecca A; Nomura, Daniel K; Durieux, Jenni; Riera, Celine E; Sanchez, Melissa; Kapernick, Erik; Wolff, Suzanne; Dillin, Andrew

    2016-09-08

    Defects in mitochondrial metabolism have been increasingly linked with age-onset protein-misfolding diseases such as Alzheimer's, Parkinson's, and Huntington's. In response to protein-folding stress, compartment-specific unfolded protein responses (UPRs) within the ER, mitochondria, and cytosol work in parallel to ensure cellular protein homeostasis. While perturbation of individual compartments can make other compartments more susceptible to protein stress, the cellular conditions that trigger cross-communication between the individual UPRs remain poorly understood. We have uncovered a conserved, robust mechanism linking mitochondrial protein homeostasis and the cytosolic folding environment through changes in lipid homeostasis. Metabolic restructuring caused by mitochondrial stress or small-molecule activators trigger changes in gene expression coordinated uniquely by both the mitochondrial and cytosolic UPRs, protecting the cell from disease-associated proteins. Our data suggest an intricate and unique system of communication between UPRs in response to metabolic changes that could unveil new targets for diseases of protein misfolding.

  8. Hormonal contraception use alters stress responses and emotional memory.

    PubMed

    Nielsen, Shawn E; Segal, Sabrina K; Worden, Ian V; Yim, Ilona S; Cahill, Larry

    2013-02-01

    Emotionally arousing material is typically better remembered than neutral material. Since norepinephrine and cortisol interact to modulate emotional memory, sex-related influences on stress responses may be related to sex differences in emotional memory. Two groups of healthy women - one naturally cycling (NC women, n=42) and one using hormonal contraceptives (HC women, n=36) - viewed emotionally arousing and neutral images. Immediately after, they were assigned to Cold Pressor Stress (CPS) or a control procedure. One week later, participants received a surprise free recall test. Saliva samples were collected and later assayed for salivary alpha-amylase (biomarker for norepinephrine) and cortisol. Compared to NC women, HC women exhibited significantly blunted stress hormone responses to the images and CPS. Recall of emotional images differed between HC and NC women depending on noradrenergic and cortisol responses. These findings may have important implications for understanding the neurobiology of emotional memory disorders, especially those that disproportionately affect women.

  9. Systems Responses to Progressive Water Stress in Durum Wheat

    PubMed Central

    Habash, Dimah Z.; Baudo, Marcela; Hindle, Matthew; Powers, Stephen J.; Defoin-Platel, Michael; Mitchell, Rowan; Saqi, Mansoor; Rawlings, Chris; Latiri, Kawther; Araus, Jose L.; Abdulkader, Ahmad; Tuberosa, Roberto; Lawlor, David W.; Nachit, Miloudi M.

    2014-01-01

    Durum wheat is susceptible to terminal drought which can greatly decrease grain yield. Breeding to improve crop yield is hampered by inadequate knowledge of how the physiological and metabolic changes caused by drought are related to gene expression. To gain better insight into mechanisms defining resistance to water stress we studied the physiological and transcriptome responses of three durum breeding lines varying for yield stability under drought. Parents of a mapping population (Lahn x Cham1) and a recombinant inbred line (RIL2219) showed lowered flag leaf relative water content, water potential and photosynthesis when subjected to controlled water stress time transient experiments over a six-day period. RIL2219 lost less water and showed constitutively higher stomatal conductance, photosynthesis, transpiration, abscisic acid content and enhanced osmotic adjustment at equivalent leaf water compared to parents, thus defining a physiological strategy for high yield stability under water stress. Parallel analysis of the flag leaf transcriptome under stress uncovered global trends of early changes in regulatory pathways, reconfiguration of primary and secondary metabolism and lowered expression of transcripts in photosynthesis in all three lines. Differences in the number of genes, magnitude and profile of their expression response were also established amongst the lines with a high number belonging to regulatory pathways. In addition, we documented a large number of genes showing constitutive differences in leaf transcript expression between the genotypes at control non-stress conditions. Principal Coordinates Analysis uncovered a high level of structure in the transcriptome response to water stress in each wheat line suggesting genome-wide co-ordination of transcription. Utilising a systems-based approach of analysing the integrated wheat’s response to water stress, in terms of biological robustness theory, the findings suggest that each durum line

  10. The Effect of Music on the Human Stress Response

    PubMed Central

    Thoma, Myriam V.; La Marca, Roberto; Brönnimann, Rebecca; Finkel, Linda; Ehlert, Ulrike; Nater, Urs M.

    2013-01-01

    Background Music listening has been suggested to beneficially impact health via stress-reducing effects. However, the existing literature presents itself with a limited number of investigations and with discrepancies in reported findings that may result from methodological shortcomings (e.g. small sample size, no valid stressor). It was the aim of the current study to address this gap in knowledge and overcome previous shortcomings by thoroughly examining music effects across endocrine, autonomic, cognitive, and emotional domains of the human stress response. Methods Sixty healthy female volunteers (mean age = 25 years) were exposed to a standardized psychosocial stress test after having been randomly assigned to one of three different conditions prior to the stress test: 1) relaxing music (‘Miserere’, Allegri) (RM), 2) sound of rippling water (SW), and 3) rest without acoustic stimulation (R). Salivary cortisol and salivary alpha-amylase (sAA), heart rate (HR), respiratory sinus arrhythmia (RSA), subjective stress perception and anxiety were repeatedly assessed in all subjects. We hypothesized that listening to RM prior to the stress test, compared to SW or R would result in a decreased stress response across all measured parameters. Results The three conditions significantly differed regarding cortisol response (p = 0.025) to the stressor, with highest concentrations in the RM and lowest in the SW condition. After the stressor, sAA (p=0.026) baseline values were reached considerably faster in the RM group than in the R group. HR and psychological measures did not significantly differ between groups. Conclusion Our findings indicate that music listening impacted the psychobiological stress system. Listening to music prior to a standardized stressor predominantly affected the autonomic nervous system (in terms of a faster recovery), and to a lesser degree the endocrine and psychological stress response. These findings may help better understanding the

  11. Thigmomorphogenetic responses of an aquatic macrophyte to hydrodynamic stress.

    PubMed

    Schoelynck, Jonas; Puijalon, Sara; Meire, Patrick; Struyf, Eric

    2015-01-01

    The response of aquatic plants to abiotic factors is a crucial study topic, because the diversity of aquatic vegetation is strongly related to specific adaptations to a variety of environments. This biodiversity ensures resilience of aquatic communities to new and changing ecological conditions. In running water, hydrodynamic disturbance is one of the key factors in this context. While plant adaptations to resource stress (nutrients, light…) are well documented, adaptations to mechanical stress, particularly flow, are largely unknown. The submerged species Egeria densa was used in an experiment to detect whether the presence or absence of hydrodynamic stress causes plant thigmomorphogenetic responses (i) in terms of plant biogenic silica (BSi), cellulose and lignin concentrations, and (ii) in terms of plant strength. Plant silica concentrations, as well as lignin concentrations were significantly higher in presence of hydrodynamic stress. These physiological changes are accompanied by some significant changes in stem biomechanical traits: stem resistance to tensile forces (breaking force and breaking strength) and stiffness were higher for plants exposed to hydrodynamic stress. We conclude that the response of this aquatic plant species to mechanical stress is likely the explaining factor for a higher capacity to tolerate stress through the production of mechanically hardened shoots.

  12. Targeting oxidative stress response by green tea polyphenols: clinical implications.

    PubMed

    Yiannakopoulou, Eugenia Ch

    2013-09-01

    Green tea polyphenols, the most interesting constituent of green tea leaves, have been shown to have both pro-oxidant and antioxidant properties. Both pro-oxidant and antioxidant properties are expected to contribute to modulation of oxidative stress response under ideal optimal dosage regimens. Exposure to a low concentration of a pro-oxidant prior to exposure to oxidative stress induces the expression of genes that code for proteins that induce adaptation in a subsequent oxidative stress. On the other hand, exposure to an antioxidant concurrently with exposure to the oxidative stress affords protection through free radical scavenging or through other indirect antioxidant mechanisms. In any case, the optimal conditions that afford protection from oxidative stress should be defined for any substance with redox properties. Green tea polyphenols, being naturally occurring substances, seem to be an ideal option for the modulation of oxidative stress response. This paper reviews available data on the pro-oxidant and antioxidant properties of green tea polyphenols focusing on their potential on the modulation of oxidative stress response.

  13. Thigmomorphogenetic responses of an aquatic macrophyte to hydrodynamic stress

    PubMed Central

    Schoelynck, Jonas; Puijalon, Sara; Meire, Patrick; Struyf, Eric

    2015-01-01

    The response of aquatic plants to abiotic factors is a crucial study topic, because the diversity of aquatic vegetation is strongly related to specific adaptations to a variety of environments. This biodiversity ensures resilience of aquatic communities to new and changing ecological conditions. In running water, hydrodynamic disturbance is one of the key factors in this context. While plant adaptations to resource stress (nutrients, light…) are well documented, adaptations to mechanical stress, particularly flow, are largely unknown. The submerged species Egeria densa was used in an experiment to detect whether the presence or absence of hydrodynamic stress causes plant thigmomorphogenetic responses (i) in terms of plant biogenic silica (BSi), cellulose and lignin concentrations, and (ii) in terms of plant strength. Plant silica concentrations, as well as lignin concentrations were significantly higher in presence of hydrodynamic stress. These physiological changes are accompanied by some significant changes in stem biomechanical traits: stem resistance to tensile forces (breaking force and breaking strength) and stiffness were higher for plants exposed to hydrodynamic stress. We conclude that the response of this aquatic plant species to mechanical stress is likely the explaining factor for a higher capacity to tolerate stress through the production of mechanically hardened shoots. PMID:25699070

  14. 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.

  15. Molecular and biochemical responses of Volvox carteri to oxidative stress

    NASA Astrophysics Data System (ADS)

    Lingappa, U.; Rankin-Gee, E. K.; Lera, M.; Bebour, B.; Marcu, O.

    2014-03-01

    Understanding the intracellular response to environmental stresses is a key aspect to understanding the limits of habitability for life as we know it. A wide range of relevant stressors, from heat shock to radiation, result in the intracellular production of reactive oxygen species (ROS). ROS are used physiologically as signaling molecules to cause changes in gene expression and metabolism. However, ROS, including superoxide (O2-) and peroxides, are also highly reactive molecules that cause oxidative damage to proteins, lipids and DNA. Here we studied stress response in the multicellular, eukaryotic green alga Volvox carteri, after exposure to heat shock conditions. We show that the ROS response to heat stress is paralleled by changes in photosynthetic metabolism, antioxidant enzyme activity and gene expression, and fluctuations in the elemental composition of cells. Metabolism, as measured by pulse amplitude modulated (PAM) fluorometry over two hours of heat stress, showed a linear decrease in the photosynthetic efficiency of Volvox. ROS quantification uncovered an increase in ROS in the culture medium, paralleled by a decrease in ROS within the Volvox colonies, suggesting an export mechanism is utilized to mitigate stress. Enzyme kinetics indicated an increase in superoxide dismutase (SOD) activity over the heat stress timecourse. Using X-ray fluorescence (XRF) at the Stanford Synchrotron Radiation Lightsource, we show that these changes coincide with cell-specific import/export and intracellular redistribution of transition elements and halides, suggesting that the cellular metallome is also engaged in mediating oxidative stress in Volvox.

  16. Differentiating anticipatory from reactive cortisol responses to psychosocial stress.

    PubMed

    Engert, Veronika; Efanov, Simona I; Duchesne, Annie; Vogel, Susanne; Corbo, Vincent; Pruessner, Jens C

    2013-08-01

    Most psychosocial stress studies assess the overall cortisol response without further identifying the temporal dynamics within hormone levels. It has been shown, however, that the amplitude of anticipatory cortisol stress levels has a unique predictive value for psychological health. So far, no "best practice" in how to investigate the anticipatory cortisol stress response has emerged. The goal of the current research was to develop a protocol that would allow for a sensitive and easy-to-implement laboratory-based investigation into anticipatory cortisol stress levels. We initially tested 26 healthy men in either an anticipation- or stress-only condition of the Trier Social Stress Test (TSST) to map the distinct timelines of anticipatory and reactive cortisol release profiles (study 1). Subsequently, we administered the TSST to 50 healthy men such that the cortisol responses to anticipatory and reactive stress components could be dissociated (study 2). In both studies we sampled saliva cortisol at high frequency (at baseline, during 10min of anticipation and during and after 10min of acute stress) and the current mood state pre- and post-stress. We found anticipatory responder rates of 20% and 40%, with peak anticipatory cortisol levels between 14 and 20min after onset of anticipation. Visible changes in reactive cortisol levels occurred only after the termination of the acute stressor. We conclude that the best practice to detect a maximum number of anticipatory responders in the TSST would be to extend the anticipation phase to 15min. In doing so, the anticipatory cortisol peak could be captured at a time-point of the actual stressor that is uninfluenced by reactive cortisol levels. Overall, we could reveal several features of anticipatory responders. Most importantly, there was a positive correlation between anticipatory and reactive stress responses. There was no association between anticipatory cortisol and alpha-amylase as well as subjective

  17. Characterizing and Targeting Replication Stress Response Defects in Breast Cancer

    DTIC Science & Technology

    2015-08-01

    oncogene activation or loss of tumor suppressor genes induces stalling and collapse of DNA replication forks, which in turn activates the replication...stress response (RSR) to maintain genome integrity [1-4]. RSR is a subset of the DNA damage response that safeguards the replication process [5]; defects...Taiwan, and one poster presentation by my postdoctoral fellow at the Conference of Exploring DNA Repair Pathways as Targets for Cancer at Cancun

  18. Immune and stress responses in oysters with insights on adaptation.

    PubMed

    Guo, Ximing; He, Yan; Zhang, Linlin; Lelong, Christophe; Jouaux, Aude

    2015-09-01

    Oysters are representative bivalve molluscs that are widely distributed in world oceans. As successful colonizers of estuaries and intertidal zones, oysters are remarkably resilient against harsh environmental conditions including wide fluctuations in temperature and salinity as well as prolonged air exposure. Oysters have no adaptive immunity but can thrive in microbe-rich estuaries as filter-feeders. These unique adaptations make oysters interesting models to study the evolution of host-defense systems. Recent advances in genomic studies including sequencing of the oyster genome have provided insights into oyster's immune and stress responses underlying their amazing resilience. Studies show that the oyster genomes are highly polymorphic and complex, which may be key to their resilience. The oyster genome has a large gene repertoire that is enriched for immune and stress response genes. Thousands of genes are involved in oyster's immune and stress responses, through complex interactions, with many gene families expanded showing high sequence, structural and functional diversity. The high diversity of immune receptors and effectors may provide oysters with enhanced specificity in immune recognition and response to cope with diverse pathogens in the absence of adaptive immunity. Some members of expanded immune gene families have diverged to function at different temperatures and salinities or assumed new roles in abiotic stress response. Most canonical innate immunity pathways are conserved in oysters and supported by a large number of diverse and often novel genes. The great diversity in immune and stress response genes exhibited by expanded gene families as well as high sequence and structural polymorphisms may be central to oyster's adaptation to highly stressful and widely changing environments.

  19. Glycerol stress in Saccharomyces cerevisiae: Cellular responses and evolved adaptations.

    PubMed

    Mattenberger, Florian; Sabater-Muñoz, Beatriz; Hallsworth, John E; Fares, Mario A

    2017-03-01

    Glycerol synthesis is key to central metabolism and stress biology in Saccharomyces cerevisiae, yet the cellular adjustments needed to respond and adapt to glycerol stress are little understood. Here, we determined impacts of acute and chronic exposures to glycerol stress in S. cerevisiae. Glycerol stress can result from an increase of glycerol concentration in the medium due to the S. cerevisiae fermenting activity or other metabolic activities. Acute glycerol-stress led to a 50% decline in growth rate and altered transcription of more than 40% of genes. The increased genetic diversity in S. cerevisiae population, which had evolved in the standard nutrient medium for hundreds of generations, led to an increase in growth rate and altered transcriptome when such population was transferred to stressful media containing a high concentration of glycerol; 0.41 M (0.990 water activity). Evolution of S. cerevisiae populations during a 10-day period in the glycerol-containing medium led to transcriptome changes and readjustments to improve control of glycerol flux across the membrane, regulation of cell cycle, and more robust stress response; and a remarkable increase of growth rate under glycerol stress. Most of the observed regulatory changes arose in duplicated genes. These findings elucidate the physiological mechanisms, which underlie glycerol-stress response, and longer-term adaptations, in S. cerevisiae; they also have implications for enigmatic aspects of the ecology of this otherwise well-characterized yeast.

  20. Stress response of brown pelican nestlings to ectoparasite infestation

    USGS Publications Warehouse

    Eggert, L.M.F.; Jodice, P.G.R.; O'Reilly, K. M.

    2010-01-01

    Measurement of corticosterone has become a useful tool for assessing the response of individuals to ecological stressors of interest. Enhanced corticosterone levels can promote survival of stressful events; however, in situations where a stressor persists and corticosterone levels remain elevated, the adrenocortical response can be detrimental. A potential ecological stressor for wild birds is parasitism by ectoparasites. We studied the stress response of 11-23-day-old brown pelican (Pelecanus occidentalis) nestlings by measuring plasma corticosterone levels in relation to the presence of the soft tick Carios capensis at two colonies in South Carolina in 2005. We expected to see higher baseline and stress-induced levels of corticosterone for parasitized chicks compared to those nestlings with no ticks. Although nestlings mounted a response to capture stress, tick category was not associated with corticosterone levels at either colony. Our results appear to contrast those of previous studies and indicate that the adrenocortical response of the host is likely dependent on the type of ectoparasite and the degree of infestation. ?? 2009 Elsevier Inc.

  1. Dysregulation of the stress response in asthmatic children.

    PubMed

    Priftis, K N; Papadimitriou, A; Nicolaidou, P; Chrousos, G P

    2009-01-01

    The stress system co-ordinates the adaptive responses of the organism to stressors of any kind. Inappropriate responsiveness may account for increased susceptibility to a variety of disorders, including asthma. Accumulated evidence from animal models suggests that exogenously applied stress enhances airway reactivity and increases allergen-induced airway inflammation. This is in agreement with the clinical observation that stressful life events increase the risk of a new asthma attack. Activation of the hypothalamic-pituitary-adrenal (HPA) axis by specific cytokines increases the release of cortisol, which in turn feeds back and suppresses the immune reaction. Data from animal models suggest that inability to increase glucocorticoid production in response to stress is associated with increased airway inflammation with mechanical dysfunction of the lungs. Recently, a growing body of evidence shows that asthmatic subjects who are not treated with inhaled corticosteroids (ICS) are likely to have an attenuated activity and/or responsiveness of their HPA axis. In line with this concept, most asthmatic children demonstrate improved HPA axis responsiveness on conventional doses of ICS, as their airway inflammation subsides. Few patients may experience further deterioration of adrenal function, a phenomenon which may be genetically determined.

  2. Oxidative stress response pathways: Fission yeast as archetype.

    PubMed

    Papadakis, Manos A; Workman, Christopher T

    2015-01-01

    Schizosaccharomyces pombe is a popular model eukaryotic organism to study diverse aspects of mammalian biology, including responses to cellular stress triggered by redox imbalances within its compartments. The review considers the current knowledge on the signaling pathways that govern the transcriptional response of fission yeast cells to elevated levels of hydrogen peroxide. Particular attention is paid to the mechanisms that yeast cells employ to promote cell survival in conditions of intermediate and acute oxidative stress. The role of the Sty1/Spc1/Phh1 mitogen-activated protein kinase in regulating gene expression at multiple levels is discussed in detail.

  3. Thermodynamic Modeling and Analysis of Human Stress Response

    NASA Technical Reports Server (NTRS)

    Boregowda, S. C.; Tiwari, S. N.

    1999-01-01

    A novel approach based on the second law of thermodynamics is developed to investigate the psychophysiology and quantify human stress level. Two types of stresses (thermal and mental) are examined. A Unified Stress Response Theory (USRT) is developed under the new proposed field of study called Engineering Psychophysiology. The USRT is used to investigate both thermal and mental stresses from a holistic (human body as a whole) and thermodynamic viewpoint. The original concepts and definitions are established as postulates which form the basis for thermodynamic approach to quantify human stress level. An Objective Thermal Stress Index (OTSI) is developed by applying the second law of thermodynamics to the human thermal system to quantify thermal stress or dis- comfort in the human body. The human thermal model based on finite element method is implemented. It is utilized as a "Computational Environmental Chamber" to conduct series of simulations to examine the human thermal stress responses under different environmental conditions. An innovative hybrid technique is developed to analyze human thermal behavior based on series of human-environment interaction simulations. Continuous monitoring of thermal stress is demonstrated with the help of OTSI. It is well established that the human thermal system obeys the second law of thermodynamics. Further, the OTSI is validated against the experimental data. Regarding mental stress, an Objective Mental Stress Index (OMSI) is developed by applying the Maxwell relations of thermodynamics to the combined thermal and cardiovascular system in the human body. The OMSI is utilized to demonstrate the technique of monitoring mental stress continuously and is validated with the help of series of experimental studies. Although the OMSI indicates the level of mental stress, it provides a strong thermodynamic and mathematical relationship between activities of thermal and cardiovascular systems of the human body.

  4. Transcriptional responses of Arabidopsis thaliana plants to As (V) stress

    PubMed Central

    Abercrombie, Jason M; Halfhill, Matthew D; Ranjan, Priya; Rao, Murali R; Saxton, Arnold M; Yuan, Joshua S; Stewart, C Neal

    2008-01-01

    Background Arsenic is toxic to plants and a common environmental pollutant. There is a strong chemical similarity between arsenate [As (V)] and phosphate (Pi). Whole genome oligonucleotide microarrays were employed to investigate the transcriptional responses of Arabidopsis thaliana plants to As (V) stress. Results Antioxidant-related genes (i.e. coding for superoxide dismutases and peroxidases) play prominent roles in response to arsenate. The microarray experiment revealed induction of chloroplast Cu/Zn superoxide dismutase (SOD) (at2g28190), Cu/Zn SOD (at1g08830), as well as an SOD copper chaperone (at1g12520). On the other hand, Fe SODs were strongly repressed in response to As (V) stress. Non-parametric rank product statistics were used to detect differentially expressed genes. Arsenate stress resulted in the repression of numerous genes known to be induced by phosphate starvation. These observations were confirmed with qRT-PCR and SOD activity assays. Conclusion Microarray data suggest that As (V) induces genes involved in response to oxidative stress and represses transcription of genes induced by phosphate starvation. This study implicates As (V) as a phosphate mimic in the cell by repressing genes normally induced when available phosphate is scarce. Most importantly, these data reveal that arsenate stress affects the expression of several genes with little or unknown biological functions, thereby providing new putative gene targets for future research. PMID:18684332

  5. Mitochondrial DNA Stress Primes the Antiviral Innate Immune Response

    PubMed Central

    West, A. Phillip; Khoury-Hanold, William; Staron, Matthew; Tal, Michal C.; Pineda, Cristiana M.; Lang, Sabine M.; Bestwick, Megan; Duguay, Brett A.; Raimundo, Nuno; MacDuff, Donna A.; Kaech, Susan M.; Smiley, James R.; Means, Robert E.; Iwasaki, Akiko; Shadel, Gerald S.

    2014-01-01

    Mitochondrial DNA (mtDNA) is normally present at thousands of copies per cell and is packaged into several hundred higher-order structures termed nucleoids1. The abundant mtDNA-binding protein, transcription factor A mitochondrial (TFAM), regulates nucleoid architecture, abundance, and segregation2. Complete mtDNA depletion profoundly impairs oxidative phosphorylation (OXPHOS), triggering calcium-dependent stress signaling and adaptive metabolic responses3. However, the cellular responses to mtDNA instability, a physiologically relevant stress observed in many human diseases and aging, remain ill-defined4. Here we show that moderate mtDNA stress elicited by TFAM deficiency engages cytosolic antiviral signaling to enhance the expression of a subset of interferon-stimulated genes (ISG). Mechanistically, we have found that aberrant mtDNA packaging promotes escape of mtDNA into the cytosol, where it engages the DNA sensor cGAS and promotes STING-IRF3-dependent signaling to elevate ISG expression, potentiate type I interferon responses, and confer broad viral resistance. Furthermore, we demonstrate that herpesviruses induce mtDNA stress, which potentiates antiviral signaling and type I interferon responses during infection. Our results further demonstrate that mitochondria are central participants in innate immunity, identify mtDNA stress as a cell-intrinsic trigger of antiviral signaling, and suggest that cellular monitoring of mtDNA homeostasis cooperates with canonical virus sensing mechanisms to fully license antiviral innate immunity. PMID:25642965

  6. 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'.

  7. Proteomics Analysis of Alfalfa Response to Heat Stress

    PubMed Central

    Li, Weimin; Wei, Zhenwu; Qiao, Zhihong; Wu, Zinian; Cheng, Lixiang; Wang, Yuyang

    2013-01-01

    The proteome responses to heat stress have not been well understood. In this study, alfalfa (Medicago sativa L. cv. Huaiyin) seedlings were exposed to 25°C (control) and 40°C (heat stress) in growth chambers, and leaves were collected at 24, 48 and 72 h after treatment, respectively. The morphological, physiological and proteomic processes were negatively affected under heat stress. Proteins were extracted and separated by two-dimensional polyacrylamide gel electrophoresis (2-DE), and differentially expressed protein spots were identified by mass spectrometry (MS). Totally, 81 differentially expressed proteins were identified successfully by MALDI-TOF/TOF. These proteins were categorized into nine classes: including metabolism, energy, protein synthesis, protein destination/storage, transporters, intracellular traffic, cell structure, signal transduction and disease/defence. Five proteins were further analyzed for mRNA levels. The results of the proteomics analyses provide a better understanding of the molecular basis of heat-stress responses in alfalfa. PMID:24324825

  8. Chronic Stress Decreases Cerebrovascular Responses During Rat Hindlimb Electrical Stimulation

    PubMed Central

    Lee, Sohee; Kang, Bok-Man; Shin, Min-Kyoo; Min, Jiwoong; Heo, Chaejeong; Lee, Yubu; Baeg, Eunha; Suh, Minah

    2015-01-01

    Repeated stress is one of the major risk factors for cerebrovascular disease, including stroke, and vascular dementia. However, the functional alterations in the cerebral hemodynamic response induced by chronic stress have not been clarified. Here, we investigated the in vivo cerebral hemodynamic changes and accompanying cellular and molecular changes in chronically stressed rats. After 3 weeks of restraint stress, the elicitation of stress was verified by behavioral despair in the forced swimming test and by physical indicators of stress. The evoked changes in the cerebral blood volume and pial artery responses following hindpaw electrical stimulation were measured using optical intrinsic signal imaging. We observed that, compared to the control group, animals under chronic restraint stress exhibited a decreased hemodynamic response, with a smaller pial arterial dilation in the somatosensory cortex during hindpaw electrical stimulation. The effect of chronic restraint stress on vasomodulator enzymes, including neuronal nitric oxide synthase (nNOS) and heme oxygenase-2 (HO-2), was assessed in the somatosensory cortex. Chronic restraint stress downregulated nNOS and HO-2 compared to the control group. In addition, we examined the subtypes of cells that can explain the environmental changes due to the decreased vasomodulators. The expression of parvalbumin in GABAergic interneurons and glutamate receptor-1 in neurons were decreased, whereas the microglial activation was increased. Our results suggest that the chronic stress-induced alterations in cerebral vascular function and the modulations of the cellular expression in the neuro-vasomodulatory system may be crucial contributing factors in the development of various vascular-induced conditions in the brain. PMID:26778944

  9. 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

  10. Endogenous nociceptin system involvement in stress responses and anxiety behavior.

    PubMed

    Fulford, Allison Jane

    2015-01-01

    The mechanisms underpinning stress-related behavior and dysfunctional events leading to the expression of neuropsychiatric disorders remain incompletely understood. Novel candidates involved in the neuromodulation of stress, mediated both peripherally and centrally, provide opportunities for improved understanding of the neurobiological basis of stress disorders and may represent targets for novel therapeutic development. This chapter provides an overview of the mechanisms by which the opioid-related peptide, nociceptin, regulates the neuroendocrine stress response and stress-related behavior. In our research, we have employed nociceptin receptor antagonists to investigate endogenous nociceptin function in tonic control over stress-induced activity of the hypothalamo-pituitary-adrenal axis. Nociceptin demonstrates a wide range of functions, including modulation of psychological and inflammatory stress responses, modulation of neurotransmitter release, immune homeostasis, in addition to anxiety and cognitive behaviors. Greater appreciation of the complexity of limbic-hypothalamic neuronal networks, together with attention toward gender differences and the roles of steroid hormones, provides an opportunity for deeper understanding of the importance of the nociceptin system in the context of the neurobiology of stress and behavior.

  11. Models and Methods to Investigate Acute Stress Responses in Cattle

    PubMed Central

    Chen, Yi; Arsenault, Ryan; Napper, Scott; Griebel, Philip

    2015-01-01

    There is a growing appreciation within the livestock industry and throughout society that animal stress is an important issue that must be addressed. With implications for animal health, well-being, and productivity, minimizing animal stress through improved animal management procedures and/or selective breeding is becoming a priority. Effective management of stress, however, depends on the ability to identify and quantify the effects of various stressors and determine if individual or combined stressors have distinct biological effects. Furthermore, it is critical to determine the duration of stress-induced biological effects if we are to understand how stress alters animal production and disease susceptibility. Common stress models used to evaluate both psychological and physical stressors in cattle are reviewed. We identify some of the major gaps in our knowledge regarding responses to specific stressors and propose more integrated methodologies and approaches to measuring these responses. These approaches are based on an increased knowledge of both the metabolic and immune effects of stress. Finally, we speculate on how these findings may impact animal agriculture, as well as the potential application of large animal models to understanding human stress. PMID:26633525

  12. Endoplasmic reticulum stress response in yeast and humans

    PubMed Central

    Wu, Haoxi; Ng, Benjamin S. H.; Thibault, Guillaume

    2014-01-01

    Stress pathways monitor intracellular systems and deploy a range of regulatory mechanisms in response to stress. One of the best-characterized pathways, the UPR (unfolded protein response), is an intracellular signal transduction pathway that monitors ER (endoplasmic reticulum) homoeostasis. Its activation is required to alleviate the effects of ER stress and is highly conserved from yeast to human. Although metazoans have three UPR outputs, yeast cells rely exclusively on the Ire1 (inositol-requiring enzyme-1) pathway, which is conserved in all Eukaryotes. In general, the UPR program activates hundreds of genes to alleviate ER stress but it can lead to apoptosis if the system fails to restore homoeostasis. In this review, we summarize the major advances in understanding the response to ER stress in Sc (Saccharomyces cerevisiae), Sp (Schizosaccharomyces pombe) and humans. The contribution of solved protein structures to a better understanding of the UPR pathway is discussed. Finally, we cover the interplay of ER stress in the development of diseases. PMID:24909749

  13. The ethanol stress response and ethanol tolerance of Saccharomyces cerevisiae.

    PubMed

    Stanley, D; Bandara, A; Fraser, S; Chambers, P J; Stanley, G A

    2010-07-01

    Saccharomyces cerevisiae is traditionally used for alcoholic beverage and bioethanol production; however, its performance during fermentation is compromised by the impact of ethanol accumulation on cell vitality. This article reviews studies into the molecular basis of the ethanol stress response and ethanol tolerance of S. cerevisiae; such knowledge can facilitate the development of genetic engineering strategies for improving cell performance during ethanol stress. Previous studies have used a variety of strains and conditions, which is problematic, because the impact of ethanol stress on gene expression is influenced by the environment. There is however some commonality in Gene Ontology categories affected by ethanol assault that suggests that the ethanol stress response of S. cerevisiae is compromised by constraints on energy production, leading to increased expression of genes associated with glycolysis and mitochondrial function, and decreased gene expression in energy-demanding growth-related processes. Studies using genome-wide screens suggest that the maintenance of vacuole function is important for ethanol tolerance, possibly because of the roles of this organelle in protein turnover and maintaining ion homoeostasis. Accumulation of Asr1 and Rat8 in the nucleus specifically during ethanol stress suggests S. cerevisiae has a specific response to ethanol stress although this supposition remains controversial.

  14. Arterial stiffness and inflammatory response to psychophysiological stress.

    PubMed

    Ellins, Elizabeth; Halcox, Julian; Donald, Ann; Field, Bryony; Brydon, Lena; Deanfield, John; Steptoe, Andrew

    2008-08-01

    The processes through which psychological stress influences cardiovascular disease are poorly understood, but may involve activation of hemodynamic, neuroendocrine and inflammatory responses. We assessed the relationship between carotid arterial stiffness and inflammatory responses to acute psychophysiologic stress. Participants were 155 healthy men and women aged 55.3, SD 2.7 years. Blood samples for the assessment of plasma fibrinogen, tumor necrosis factor (TNF) alpha and interleukin (IL) 6 were drawn at baseline, immediately following standardized behavioral tasks, and 45 min later. Carotid artery stiffness was measured ultrasonically three years later, and blood pressure and heart rate responses were recorded. The tasks induced substantial increases in blood pressure and heart rate, together with increased fibrinogen, TNFalpha and IL-6 concentration. Carotid stiffness was positively associated with body mass, waist/hip ratio, blood pressure, low density lipoprotein cholesterol, and C-reactive protein, and inversely with high density lipoprotein and grade of employment. Baseline levels of inflammatory variables were not related to carotid artery stiffness. But carotid stiffness was greater in participants with larger fibrinogen (p=0.037) and TNFalpha (p=0.036) responses to psychophysiological stress. These effects were independent of age, gender, grade of employment, smoking, body mass, waist/hip ratio, systolic and diastolic pressure, high and low density lipoprotein cholesterol, and C-reactive protein. There were no associations between carotid stiffness and stress responses in IL-6, blood pressure, or heart rate. We conclude that individual differences in inflammatory responses to psychophysiological stress are independently related to structural changes in artery walls that reflect increased cardiovascular disease risk.

  15. Role of brain norepinephrine in the behavioral response to stress.

    PubMed

    Morilak, David A; Barrera, Gabe; Echevarria, David J; Garcia, April S; Hernandez, Angelica; Ma, Shuaike; Petre, Corina O

    2005-12-01

    The brain noradrenergic system is activated by acute stress. The post-synaptic effects of norepinephrine (NE), exerted at a cellular or neural circuit level, have been described as modulatory in nature, as NE facilitates responses evoked in target cells by both excitatory and inhibitory afferent input. Over the past few years, we have undertaken a series of studies to understand how these cellular modulatory effects of NE, elicited by acute stress, might translate into modulation of the behavioral-affective components of the whole-animal response to stress. Using microdialysis, we have demonstrated that acute immobilization stress activates NE release in a number of stress-related limbic forebrain target regions, such as the central and medial amygdala, lateral bed nucleus of the stria terminalis, medial prefrontal cortex, and lateral septum. Using microinjections of adrenergic antagonist drugs directly into these regions, we have shown that this stress-induced release of NE facilitates a number of anxiety-like behavioral responses that are mediated in these regions, including stress-induced reduction of open-arm exploration on the elevated plus-maze, stress-induced reduction of social interaction behavior, and activation of defensive burying behavior by contact with an electrified probe. Dysregulation of the brain noradrenergic system may be a factor in determining vulnerability to stress-related pathology, or in the interaction of genetic vulnerability and environmental sensitization. Compared to outbred Sprague-Dawley rats, we have shown that the modulatory effect of NE is deficient in Wistar-Kyoto rats, which also exhibit attenuated behavioral reactivity to acute stress, as well as increased vulnerability to stress-induced gastric ulcers and exaggerated activation of the hypothalamic-pituitary-adrenal (HPA) stress axis. Further, repeated exposure to mild intermittent cold stress resulted in a much greater sensitization of both the brain noradrenergic system and

  16. How plants handle multiple stresses: hormonal interactions underlying responses to abiotic stress and insect herbivory.

    PubMed

    Nguyen, Duy; Rieu, Ivo; Mariani, Celestina; van Dam, Nicole M

    2016-08-01

    Adaptive plant responses to specific abiotic stresses or biotic agents are fine-tuned by a network of hormonal signaling cascades, including abscisic acid (ABA), ethylene, jasmonic acid (JA) and salicylic acid. Moreover, hormonal cross-talk modulates plant responses to abiotic stresses and defenses against insect herbivores when they occur simultaneously. How such interactions affect plant responses under multiple stresses, however, is less understood, even though this may frequently occur in natural environments. Here, we review our current knowledge on how hormonal signaling regulates abiotic stress responses and defenses against insects, and discuss the few recent studies that attempted to dissect hormonal interactions occurring under simultaneous abiotic stress and herbivory. Based on this we hypothesize that drought stress enhances insect resistance due to synergistic interactions between JA and ABA signaling. Responses to flooding or waterlogging involve ethylene signaling, which likely reduces plant resistance to chewing herbivores due to its negative cross-talk with JA. However, the outcome of interactions between biotic and abiotic stress signaling is often plant and/or insect species-dependent and cannot simply be predicted based on general knowledge on the involvement of signaling pathways in single stress responses. More experimental data on non-model plant and insect species are needed to reveal general patterns and better understand the molecular mechanisms allowing plants to optimize their responses in complex environments.

  17. Stress and Bronchodilator Response in Children with Asthma

    PubMed Central

    Brehm, John M.; Ramratnam, Sima K.; Tse, Sze Man; Croteau-Chonka, Damien C.; Pino-Yanes, Maria; Rosas-Salazar, Christian; Litonjua, Augusto A.; Raby, Benjamin A.; Boutaoui, Nadia; Han, Yueh-Ying; Chen, Wei; Forno, Erick; Marsland, Anna L.; Nugent, Nicole R.; Eng, Celeste; Colón-Semidey, Angel; Alvarez, María; Acosta-Pérez, Edna; Spear, Melissa L.; Martinez, Fernando D.; Avila, Lydiana; Weiss, Scott T.; Soto-Quiros, Manuel; Ober, Carole; Nicolae, Dan L.; Barnes, Kathleen C.; Lemanske, Robert F.; Strunk, Robert C.; Liu, Andrew; London, Stephanie J.; Gilliland, Frank; Sleiman, Patrick; March, Michael; Hakonarson, Hakon; Duan, Qing Ling; Kolls, Jay K.; Fritz, Gregory K.; Hu, Donglei; Fani, Negar; Stevens, Jennifer S.; Almli, Lynn M.; Burchard, Esteban G.; Shin, Jaemin; McQuaid, Elizabeth L.; Ressler, Kerry; Canino, Glorisa

    2015-01-01

    Rationale: Stress is associated with asthma morbidity in Puerto Ricans (PRs), who have reduced bronchodilator response (BDR). Objectives: To examine whether stress and/or a gene regulating anxiety (ADCYAP1R1) is associated with BDR in PR and non-PR children with asthma. Methods: This was a cross-sectional study of stress and BDR (percent change in FEV1 after BD) in 234 PRs ages 9–14 years with asthma. We assessed child stress using the Checklist of Children’s Distress Symptoms, and maternal stress using the Perceived Stress Scale. Replication analyses were conducted in two cohorts. Polymorphisms in ADCYAP1R1 were genotyped in our study and six replication studies. Multivariable models of stress and BDR were adjusted for age, sex, income, environmental tobacco smoke, and use of inhaled corticosteroids. Measurements and Main Results: High child stress was associated with reduced BDR in three cohorts. PR children who were highly stressed (upper quartile, Checklist of Children’s Distress Symptoms) and whose mothers had high stress (upper quartile, Perceived Stress Scale) had a BDR that was 10.2% (95% confidence interval, 6.1–14.2%) lower than children who had neither high stress nor a highly stressed mother. A polymorphism in ADCYAP1R1 (rs34548976) was associated with reduced BDR. This single-nucleotide polymorphism is associated with reduced expression of the gene for the β2-adrenergic receptor (ADRB2) in CD4+ lymphocytes of subjects with asthma, and it affects brain connectivity of the amygdala and the insula (a biomarker of anxiety). Conclusions: High child stress and an ADCYAP1R1 single-nucleotide polymorphism are associated with reduced BDR in children with asthma. This is likely caused by down-regulation of ADRB2 in highly stressed children. PMID:25918834

  18. Relation between stress-precipitated seizures and the stress response in childhood epilepsy.

    PubMed

    van Campen, Jolien S; Jansen, Floor E; Pet, Milou A; Otte, Willem M; Hillegers, Manon H J; Joels, Marian; Braun, Kees P J

    2015-08-01

    The majority of patients with epilepsy report that seizures are sometimes triggered or provoked. Stress is the most frequently self-reported seizure-precipitant. The mechanisms underlying stress-sensitivity of seizures are currently unresolved. We hypothesized that stress-sensitivity of seizures relates to alteration of the stress response, which could affect neuronal excitability and hence trigger seizures. To study this, children with epilepsy between 6 and 17 years of age and healthy controls, with similar age, sex and intelligence, were exposed to a standardized acute psychosocial stressor (the Trier Social Stress Test for Children), during which salivary cortisol and sympathetic parameters were measured. Beforehand, the relation between stress and seizures in children with epilepsy was assessed by (i) a retrospective questionnaire; and (ii) a prospective 6-week diary on stress and seizure occurrence. Sixty-four children with epilepsy and 40 control subjects were included in the study. Of all children with epilepsy, 49% reported that seizures were precipitated by acute stress. Diary analysis showed a positive association between acute stress and seizures in 62% of children who experienced at least one seizure during the diary period. The acute social stress test was completed by 56 children with epilepsy and 37 control subjects. Children with sensitivity of seizures for acute stress, either determined by the questionnaire or by the prospective diary, showed a blunted cortisol response to stress compared with patients without acute stress-precipitated seizures and healthy controls (questionnaire-based F = 2.74, P = 0.018; diary-based F = 4.40, P = 0.007). No baseline differences in cortisol were observed, nor differences in sympathetic stress response. The relation between acute stress-sensitivity of seizures and the cortisol response to stress remained significant in multivariable analysis (β = -0.30, P = 0.03). Other variables associated with the acute stress

  19. The role of thyroid hormones in stress response of fish.

    PubMed

    Peter, M C Subhash

    2011-06-01

    Thyroxine (T(4)) and triiodothyronine (T(3)), the principal thyroid hormones (THs) secreted from the hypothalamic-pituitary-thyroid (HPT) axis, produce a plethora of physiologic actions in fish. The diverse actions of THs in fishes are primarily due to the sensitivity of thyroid axis to many physical, chemical and biological factors of both intrinsic and extrinsic origins. The regulation of THs homeostasis becomes more complex due to extrathyroidal deiodination pathways by which the delivery of biologically active T(3) to target cells has been controlled. As primary stress hormones and the end products of hypothalamic-pituitary-interrenal (HPI) and brain-sympathetic-chromaffin (BSC) axes, cortisol and adrenaline exert its actions on its target tissues where it promote and integrate osmotic and metabolic competence. Despite possessing specific osmoregulatory and metabolic actions at cellular and whole-body levels, THs may fine-tune these processes in accordance with the actions of hormones like cortisol and adrenaline. Evidences are presented that THs can modify the pattern and magnitude of stress response in fishes as it modifies either its own actions or the actions of stress hormones. In addition, multiple lines of evidence indicate that hypothalamic and pituitary hormones of thyroid and interrenal axes can interact with each other which in turn may regulate THs/cortisol-mediated actions. Even though it is hard to define these interactions, the magnitude of stress response in fish has been shown to be modified by the changes in the status of THs, pointing to its functional relationship with endocrine stress axes particularly with the interrenal axis. The fine-tuned mechanism that operates in fish during stressor-challenge drives the THs to play both fundamental and modulator roles in stress response by controlling osmoregulation and metabolic regulation. A major role of THs in stress response is thus evident in fish.

  20. Proteomic responses of sea urchin embryos to stressful ultraviolet radiation.

    PubMed

    Adams, N L; Campanale, J P; Foltz, K R

    2012-11-01

    Solar ultraviolet radiation (UVR, 290-400 nm) penetrates into seawater and can harm shallow-dwelling and planktonic marine organisms. Studies dating back to the 1930s revealed that echinoids, especially sea urchin embryos, are powerful models for deciphering the effects of UVR on embryonic development and how embryos defend themselves against UV-induced damage. In addition to providing a large number of synchronously developing embryos amenable to cellular, biochemical, molecular, and single-cell analyses, the purple sea urchin, Strongylocentrotus purpuratus, also offers an annotated genome. Together, these aspects allow for the in-depth study of molecular and biochemical signatures of UVR stress. Here, we review the effects of UVR on embryonic development, focusing on the early-cleavage stages, and begin to integrate data regarding single-protein responses with comprehensive proteomic assessments. Proteomic studies reveal changes in levels of post-translational modifications to proteins that respond to UVR, and identify proteins that can then be interrogated as putative targets or components of stress-response pathways. These responsive proteins are distributed among systems upon which targeted studies can now begin to be mapped. Post-transcriptional and translational controls may provide early embryos with a rapid, fine-tuned response to stress during early stages, especially during pre-blastula stages that rely primarily on maternally derived defenses rather than on responses through zygotic gene transcription.

  1. Exposure to stressful environments - Strategy of adaptive responses

    NASA Technical Reports Server (NTRS)

    Farhi, Leon E.

    1991-01-01

    Stresses such as hypoxia, water lack, and heat exposure can produce strains in more than a single organ system, in turn stimulating the body to adapt in multiple ways. Nevertheless, a general strategy of the various adaptive responses emerges when the challenges are divided into three groups: (1) conditions that affect the supply of essential molecules, (2) stresses that prevent the body from regulating properly the output of waste products such as CO2 and heat, and (3) environments that disrupt body transport systems. Problems may arise when there is a conflict between two stresses requiring conflicting adaptive changes. An alternative to adaptation, creation of microenvironment, is often favored by the animal.

  2. Genetic mapping of abiotic stress responses in sorghum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Due to rich genetic diversity for tolerance to various abiotic stress conditions, sorghum is an ideal system for genetic mapping and elucidation of genome regions that confer such response among cereal crops. Coupled with the development of DNA marker technologies and most recently the sequencing o...

  3. Adaptive Patterns of Stress Responsivity: A Preliminary Investigation

    ERIC Educational Resources Information Center

    Del Giudice, Marco; Hinnant, J. Benjamin; Ellis, Bruce J.; El-Sheikh, Mona

    2012-01-01

    The adaptive calibration model (ACM) is an evolutionary-developmental theory of individual differences in stress responsivity. In this article, we tested some key predictions of the ACM in a middle childhood sample (N = 256). Measures of autonomic nervous system activity across the sympathetic and parasympathetic branches validated the 4-pattern…

  4. The insect capa neuropeptides impact desiccation and cold stress responses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: Insects are so successful because of great resistance to environmental stress, yet little is known about how such responses may be mediated by the neuroendocrine system. Results: We provide evidence that the capability (capa) neuropeptide gene and peptide are critical mediators of desic...

  5. Stimuli-responsive electrodes detect oxidative stress and liver injury.

    PubMed

    Aran, Kiana; Parades, Jacobo; Rafi, Mohammad; Yau, Jennifer F; Acharya, Abhinav P; Zibinsky, Mikhail; Liepmann, Dorian; Murthy, Niren

    2015-02-25

    A digital point-of-care biosensor for measuring reactive oxygen species is presented based on novel reactive oxygen species responsive polymer-based electrodes. The biosensor is able to detect a drug-induced liver injury by monitoring the oxidative stress in the blood.

  6. Severe Injury Is Associated With Insulin Resistance, Endoplasmic Reticulum Stress Response, and Unfolded Protein Response

    PubMed Central

    Jeschke, Marc G.; Finnerty, Celeste C.; Herndon, David N.; Song, Juquan; Boehning, Darren; Tompkins, Ronald G.; Baker, Henry V.; Gauglitz, Gerd G.

    2012-01-01

    Objective We determined whether postburn hyperglycemia and insulin resistance are associated with endoplasmic reticulum (ER) stress/unfolded protein response (UPR) activation leading to impaired insulin receptor signaling. Background Inflammation and cellular stress, hallmarks of severely burned and critically ill patients, have been causally linked to insulin resistance in type 2 diabetes via induction of ER stress and the UPR. Methods Twenty severely burned pediatric patients were compared with 36 nonburned children. Clinical markers, protein, and GeneChip analysis were used to identify transcriptional changes in ER stress and UPR and insulin resistance–related signaling cascades in peripheral blood leukocytes, fat, and muscle at admission and up to 466 days postburn. Results Burn-induced inflammatory and stress responses are accompanied by profound insulin resistance and hyperglycemia. Genomic and protein analysis revealed that burn injury was associated with alterations in the signaling pathways that affect insulin resistance, ER/sarcoplasmic reticulum stress, inflammation, and cell growth/apoptosis up to 466 days postburn. Conclusion Burn-induced insulin resistance is associated with persistent ER/sarcoplasmic reticulum stress/UPR and subsequent suppressed insulin receptor signaling over a prolonged period of time. PMID:22241293

  7. Contrasting urban and rural heat stress responses to climate change

    NASA Astrophysics Data System (ADS)

    Fischer, E. M.; Oleson, K. W.; Lawrence, D. M.

    2012-02-01

    Hot temperatures in combination with high humidity cause human discomfort and may increase morbidity and mortality. A global climate model with an embedded urban model is used to explore the urban-rural contrast in the wet-bulb globe temperature, a heat stress index accounting for temperature and humidity. Wet-bulb globe temperatures are calculated at each model time step to resolve the heat stress diurnal cycle. The model simulates substantially higher heat stress in urban areas compared to neighbouring rural areas. Urban humidity deficit only weakly offsets the enhanced heat stress due to the large night-time urban heat island. The urban-rural contrast in heat stress is most pronounced at night and over mid-latitudes and subtropics. During heatwaves, the urban heat stress amplification is particularly pronounced. Heat stress strongly increases with doubled CO2 concentrations over both urban and rural surfaces. The tropics experience the greatest increase in number of high-heat-stress nights, despite a relatively weak ˜2°C warming. Given the lack of a distinct annual cycle and high relative humidity, the modest tropical warming leads to exceedance of the present-day record levels during more than half of the year in tropical regions, where adaptive capacity is often low. While the absolute urban and rural heat stress response to 2 × CO2 is similar, the occurrence of nights with extremely high heat stress increases more in cities than surrounding rural areas.

  8. Hypoxia inducible factors and the response to hypoxic stress

    PubMed Central

    Majmundar, Amar J.; Wong, Waihay J.; Simon, M. Celeste

    2011-01-01

    Oxygen (O2) is an essential nutrient that serves as a key substrate in cellular metabolism and bioenergetics. In a variety of physiological and pathological states, organisms encounter insufficient O2 availability, or hypoxia. In order to cope with this stress, evolutionarily conserved responses are engaged. In mammals, the primary transcriptional response to hypoxic stress is mediated by the Hypoxia-inducible factors (HIFs). While canonically regulated by prolyl hydroxylase domain-containing enzymes (PHDs), the HIFα subunits are intricately responsive to numerous other factors including Factor Inhibiting HIF-1α (FIH1), sirtuins, and metabolites. These transcription factors function in normal tissue homeostasis and impinge on critical aspects of disease progression and recovery. Insights from basic HIF biology are being translated into pharmaceuticals targeting the HIF pathway. PMID:20965423

  9. Rethinking stress: the role of mindsets in determining the stress response.

    PubMed

    Crum, Alia J; Salovey, Peter; Achor, Shawn

    2013-04-01

    This article describes 3 studies that explore the role of mindsets in the context of stress. In Study 1, we present data supporting the reliability and validity of an 8-item instrument, the Stress Mindset Measure (SMM), designed to assess the extent to which an individual believes that the effects of stress are either enhancing or debilitating. In Study 2, we demonstrate that stress mindsets can be altered by watching short, multimedia film clips presenting factual information biased toward defining the nature of stress in 1 of 2 ways (stress-is-enhancing vs. stress-is-debilitating). In Study 3, we demonstrate the effect of stress mindset on physiological and behavioral outcomes, showing that a stress-is-enhancing mindset is associated with moderate cortisol reactivity and high desire for feedback under stress. Together, these 3 studies suggest that stress mindset is a distinct and meaningful variable in determining the stress response.

  10. Exposure to Stressful Environments: Strategy of Adaptive Responses

    NASA Technical Reports Server (NTRS)

    Farhi, Leon E.

    1991-01-01

    Any new natural environment may generate a number of stresses (such as hypoxia, water lack, and heat exposure), each of which can produce strains in more than a single organ system. Every strain may in turn stimulate the body to adapt in multiple ways. Nevertheless, a general strategy of the various adaptive responses emerges when the challenges are divided into three groups. The first category includes conditions that affect the supply of essential molecules, while the second is made up by those stresses that prevent the body from regulating properly the output of waste products, such as CO2 and heat. In both classes, there is a small number of responses, similar in principle, regardless of the specific situation. The third unit is created by environments that disrupt body transport systems. Problems may arise when there is a conflict between two stresses requiring conflicting adaptive changes. An alternative to adaptation, creation of micro-environment, is often favored by the animal.

  11. Enterovirus Control of Translation and RNA Granule Stress Responses.

    PubMed

    Lloyd, Richard E

    2016-03-30

    Enteroviruses such as poliovirus (PV) and coxsackievirus B3 (CVB3) have evolved several parallel strategies to regulate cellular gene expression and stress responses to ensure efficient expression of the viral genome. Enteroviruses utilize their encoded proteinases to take over the cellular translation apparatus and direct ribosomes to viral mRNAs. In addition, viral proteinases are used to control and repress the two main types of cytoplasmic RNA granules, stress granules (SGs) and processing bodies (P-bodies, PBs), which are stress-responsive dynamic structures involved in repression of gene expression. This review discusses these processes and the current understanding of the underlying mechanisms with respect to enterovirus infections. In addition, the review discusses accumulating data suggesting linkage exists between RNA granule formation and innate immune sensing and activation.

  12. SUMO, a heavyweight player in plant abiotic stress responses.

    PubMed

    Castro, Pedro Humberto; Tavares, Rui Manuel; Bejarano, Eduardo R; Azevedo, Herlânder

    2012-10-01

    Protein post-translational modifications diversify the proteome and install new regulatory levels that are crucial for the maintenance of cellular homeostasis. Over the last decade, the ubiquitin-like modifying peptide small ubiquitin-like modifier (SUMO) has been shown to regulate various nuclear processes, including transcriptional control. In plants, the sumoylation pathway has been significantly implicated in the response to environmental stimuli, including heat, cold, drought, and salt stresses, modulation of abscisic acid and other hormones, and nutrient homeostasis. This review focuses on the emerging importance of SUMO in the abiotic stress response, summarizing the molecular implications of sumoylation and emphasizing how high-throughput approaches aimed at identifying the full set of SUMO targets will greatly enhance our understanding of the SUMO-abiotic stress association.

  13. Enterovirus Control of Translation and RNA Granule Stress Responses

    PubMed Central

    Lloyd, Richard E.

    2016-01-01

    Enteroviruses such as poliovirus (PV) and coxsackievirus B3 (CVB3) have evolved several parallel strategies to regulate cellular gene expression and stress responses to ensure efficient expression of the viral genome. Enteroviruses utilize their encoded proteinases to take over the cellular translation apparatus and direct ribosomes to viral mRNAs. In addition, viral proteinases are used to control and repress the two main types of cytoplasmic RNA granules, stress granules (SGs) and processing bodies (P-bodies, PBs), which are stress-responsive dynamic structures involved in repression of gene expression. This review discusses these processes and the current understanding of the underlying mechanisms with respect to enterovirus infections. In addition, the review discusses accumulating data suggesting linkage exists between RNA granule formation and innate immune sensing and activation. PMID:27043612

  14. Regional cutaneous microvascular flow responses during gravitational and LBNP stresses

    NASA Technical Reports Server (NTRS)

    Breit, Gregory A.; Watenpaugh, Donald E.; Ballard, Richard E.; Murthy, Gita; Hargens, Alan R.

    1993-01-01

    Due to the regional variability of local hydrostatic pressures, microvascular flow responses to gravitational stress probably vary along the length of the body. Although these differences in local autoregulation have been observed previously during whole-body tilting, they have not been investigated during application of artificial gravitational stresses, such as lower body negative pressure or high gravity centrifugation. Although these stresses can create equivalent G-levels at the feet, they result in distinct distributions of vascular transmural pressure along the length of the body, and should consequently elicit different magnitudes and distributions of microvascular response. In the present study, the effects of whole-body tilting and lower body negative pressure on the level and distribution of microvascular flows within skin along the length of the body were compared.

  15. Salivary Markers of Inflammation in Response to Acute Stress

    PubMed Central

    Slavish, Danica C.; Graham-Engeland, Jennifer E.; Smyth, Joshua M.; Engeland, Christopher G.

    2014-01-01

    There is burgeoning interest in the ability to detect inflammatory markers in response to stress within naturally occurring social contexts and/or across multiple time points per day within individuals. Salivary collection is a less invasive process than current methods of blood collection and enables intensive naturalistic methodologies, such as those involving extensive repeated measures per day over time. Yet the reliability and validity of saliva-based to blood-based inflammatory biomarkers in response to stress remains unclear. We review and synthesize the published studies that have examined salivary markers of inflammation following exposure to an acute laboratory stressor. Results from each study are reviewed by analyte (IL-1β, TNF-α, IL-6, IL-2, IL-4, IL-10, IL-12, CRP) and stress type (social-cognitive and exercise-physical), after which methodological issues and limitations are addressed. Although the literature is limited, several inflammatory markers (including IL-1β, TNF-α, and IL-6) have been reliably determined from saliva and have increased significantly in response to stress across multiple studies, with effect sizes ranging from very small to very large. Although CRP from saliva has been associated with CRP in circulating blood more consistently than other biomarkers have been associated with their counterparts in blood, evidence demonstrating it reliably responds to acute stress is absent. Although the current literature is presently too limited to allow broad assertion that inflammatory biomarkers determined from saliva are valuable for examining acute stress responses, this review suggests that specific targets may be valid and highlights specific areas of need for future research. PMID:25205395

  16. Interaction between Nitrogen and Phosphate Stress Responses in Sinorhizobium meliloti

    PubMed Central

    Hagberg, Kelly L.; Yurgel, Svetlana N.; Mulder, Monika; Kahn, Michael L.

    2016-01-01

    Bacteria have developed various stress response pathways to improve their assimilation and allocation of limited nutrients, such as nitrogen and phosphate. While both the nitrogen stress response (NSR) and phosphate stress response (PSR) have been studied individually, there are few experiments reported that characterize effects of multiple stresses on one or more pathways in Sinorhizobium meliloti, a facultatively symbiotic, nitrogen-fixing bacteria. The PII proteins, GlnB and GlnK, regulate the NSR activity, but analysis of global transcription changes in a PII deficient mutant suggest that the S. meliloti PII proteins may also regulate the PSR. PII double deletion mutants grow very slowly and pseudoreversion of the slow growth phenotype is common. To understand this phenomenon better, transposon mutants were isolated that had a faster growing phenotype. One mutation was in phoB, the response regulator for a two component regulatory system that is important in the PSR. phoB::Tn5 mutants had different phenotypes in the wild type compared to a PII deficient background. This led to the hypothesis that phosphate stress affects the NSR and conversely, that nitrogen stress affects the PSR. Our results show that phosphate availability affects glutamine synthetase activity and expression, which are often used as indicators of NSR activity, but that nitrogen availability did not affect alkaline phosphatase activity and expression, which are indicators of PSR activity. We conclude that the NSR is co-regulated by nitrogen and phosphate, whereas the PSR does not appear to be co-regulated by nitrogen in addition to its known phosphate regulation. PMID:27965651

  17. Neuroendocrine responses to psychological stress in eumenorrheic and oligomenorrheic women.

    PubMed

    McComb, Jacalyn J Robert; Qian, Xu-Ping; Veldhuis, Johannes D; J McGlone, John; Norman, Reid L

    2006-03-01

    Neuroendocrine adaptive responses to psychological stress include activation of the hypothalamic-pituitary-adrenal (HPA) axis and sometimes suppression of the hypothalamic-pituitary-gonadal (HPG) axis. In women who experience chronic stress, these responses are probably responsible for disturbances in the menstrual cycle. In the present experiment, we investigated the effect of an acutely stressful situation on the physiological and neuroendocrine responses in college age women. We hypothesized that females who are experiencing some degree of abnormal menstrual function or women who have less-robust cycles (oligomenorrheic females) would exhibit differences in gonadotropin secretion from eumenorrheic females when exposed to psychological stressors. Fifteen women completed this study: eumenorrheic (n = 5) and oligomenorrheic women (n = 5) who experienced a series of psychological stressors, and eumenorrheic controls (n = 5). Blood samples were taken at 10 min intervals for 8 h (09:00-17:00) in each woman during the mid-follicular phase of the menstrual cycle. The psychological stressors were administered for 1 h beginning at 13:00 h. Luteinizing hormone (LH), growth hormone (GH) and cortisol were measured in each sample to assess the effect of stress on secretion of these hormones. Deconvolution analysis was used to analyze pulsatile hormone secretion and the approximate entropy (ApEn) statistic analyzed the regularity of release of each hormone. Although, there were significant changes in heart rate (HR), skin resistance (SR) and cortisol levels in the stressed women during the psychological stressor compared to resting baseline values but not in the controls, there was no difference in either LH or GH secretion between women who experienced stress and those who did not. Furthermore, there were no differences in the LH or GH secretion patterns in the oligomenorrheic and eumenorrheic women exposed to the psychological stressor.

  18. Tolerant and Susceptible Sesame Genotypes Reveal Waterlogging Stress Response Patterns

    PubMed Central

    Wang, Linhai; Li, Donghua; Zhang, Yanxin; Gao, Yuan; Yu, Jingyin; Wei, Xin; Zhang, Xiurong

    2016-01-01

    Waterlogging is a common adverse environmental condition that limits plant growth. Sesame (Sesamum indicum) is considered a drought-tolerant oil crop but is typically susceptible to harmful effects from waterlogging. The present study used comparative analysis to explore the waterlogging stress response associated with two sesame genotypes. The RNA-seq dataset generated during a time course of 0, 3, 9 and 15 h of waterlogging as well as 20 h post-drainage indicated that stress gradually suppressed the expression of sesame genes, with 9 h as the critical time point for the response of sesame to waterlogging stress. Of the 19,316 genes expressed during waterlogging, 72.1% were affected significantly. Sesame of both tolerant and susceptible genotypes showed decreased numbers of upregulated differentially expressed genes (DEGs) but increased numbers of downregulated DEGs at the onset of waterlogging. However, the tolerant-genotype sesame exhibited 25.5% more upregulated DEGs and 29.7% fewer downregulated DEGs than those of the susceptible-genotype strain between 3 and 15 h. The results indicated that the tolerant sesame displayed a more positive gene response to waterlogging. A total of 1,379 genes were significantly induced and commonly expressed in sesame under waterlogging conditions from 3 to 15 h regardless of tolerance level; of these genes, 98 are known homologous stress responsive genes, while the remaining 1,281 are newly reported here. This gene set may represent the core genes that function in response to waterlogging, including those related mainly to energy metabolism and phenylpropanoid biosynthesis. Furthermore, a set of 3,016 genes functioning in energy supply and cell repair or formation was activated in sesame recovery from waterlogging stress. A comparative analysis between sesame of the tolerant and susceptible genotypes revealed 66 genes that may be candidates for improving sesame tolerance to waterlogging. This study provided a comprehensive

  19. Tolerant and Susceptible Sesame Genotypes Reveal Waterlogging Stress Response Patterns.

    PubMed

    Wang, Linhai; Li, Donghua; Zhang, Yanxin; Gao, Yuan; Yu, Jingyin; Wei, Xin; Zhang, Xiurong

    2016-01-01

    Waterlogging is a common adverse environmental condition that limits plant growth. Sesame (Sesamum indicum) is considered a drought-tolerant oil crop but is typically susceptible to harmful effects from waterlogging. The present study used comparative analysis to explore the waterlogging stress response associated with two sesame genotypes. The RNA-seq dataset generated during a time course of 0, 3, 9 and 15 h of waterlogging as well as 20 h post-drainage indicated that stress gradually suppressed the expression of sesame genes, with 9 h as the critical time point for the response of sesame to waterlogging stress. Of the 19,316 genes expressed during waterlogging, 72.1% were affected significantly. Sesame of both tolerant and susceptible genotypes showed decreased numbers of upregulated differentially expressed genes (DEGs) but increased numbers of downregulated DEGs at the onset of waterlogging. However, the tolerant-genotype sesame exhibited 25.5% more upregulated DEGs and 29.7% fewer downregulated DEGs than those of the susceptible-genotype strain between 3 and 15 h. The results indicated that the tolerant sesame displayed a more positive gene response to waterlogging. A total of 1,379 genes were significantly induced and commonly expressed in sesame under waterlogging conditions from 3 to 15 h regardless of tolerance level; of these genes, 98 are known homologous stress responsive genes, while the remaining 1,281 are newly reported here. This gene set may represent the core genes that function in response to waterlogging, including those related mainly to energy metabolism and phenylpropanoid biosynthesis. Furthermore, a set of 3,016 genes functioning in energy supply and cell repair or formation was activated in sesame recovery from waterlogging stress. A comparative analysis between sesame of the tolerant and susceptible genotypes revealed 66 genes that may be candidates for improving sesame tolerance to waterlogging. This study provided a comprehensive

  20. Chronic Heat Stress Induces Immune Response, Oxidative Stress Response, and Apoptosis of Finishing Pig Liver: A Proteomic Approach.

    PubMed

    Cui, Yanjun; Hao, Yue; Li, Jielei; Bao, Weiguang; Li, Gan; Gao, Yanli; Gu, Xianhong

    2016-05-11

    Heat stress (HS) negatively affects human health, animal welfare, and livestock production. We analyzed the hepatic proteomes of finishing pigs subjected to chronic heat stress (HS), thermal neutral (TN), and restricted feed intake conditions, identifying differences between direct and indirect (via reduced feed intake) HS. Twenty-four castrated male pigs were randomly allocated to three treatments for three weeks: (1) thermal neutral (TN) (22 °C) with ad libitum feeding; (2) chronic HS (30 °C) with ad libitum feeding; and (3) TN, pair-fed to HS intake (PF). Hepatic proteome analysis was conducted using two-dimensional gel electrophoresis and mass spectrometry. Both HS and PF significantly reduced liver weight (p < 0.05). Forty-five hepatic proteins were differentially abundant when comparing HS with TN (37), PF with TN (29), and HS with PF (16). These proteins are involved in heat shock response and immune defense, oxidative stress response, cellular apoptosis, metabolism, signal transduction, and cytoskeleton. We also observed increased abundance of proteins and enzymes associated with heat shock response and immune defense, reduced the redox state, enhanced multiple antioxidant abilities, and increased apoptosis in HS liver. Heat-load, independent of reduced feed intake, induced an innate immune response, while food restriction caused stress and cellular apoptosis. Our results provide novel insights into the effects of chronic HS on liver.

  1. 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.

  2. Untranslated regions (UTRs) orchestrate translation reprogramming in cellular stress responses.

    PubMed

    Sajjanar, Basavaraj; Deb, Rajib; Raina, Susheel Kumar; Pawar, Sachin; Brahmane, Manoj P; Nirmale, Avinash V; Kurade, Nitin P; Manjunathareddy, Gundallahalli B; Bal, Santanu Kumar; Singh, Narendra Pratap

    2017-04-01

    Stress is the result of an organism's interaction with environmental challenges. Regulations of gene expression including translation modulations are critical for adaptation and survival under stress. Untranslated regions (UTRs) of the transcripts play significant roles in translation regulation and continue to raise many intriguing questions in our understanding of cellular stress physiology. IRES (Internal ribosome entry site) and uORF (upstream open reading frame) mediated alternative translation initiations are emerging as unique mechanisms. Recent studies have revealed novel means of mRNAs stabilization in stress granules and their reversible modifications. Differential regulation of select transcripts is possible by the interplay between the adenine/uridine-rich elements (AREs) in 3'UTR with their binding proteins (AUBP) and by microRNA-mediated effects. Coordination of these various mechanisms control translation and thereby enables appropriate responses to environmental stress. In this review, we focus on the role of sequence signatures both at 5' and 3'UTRs in translation reprogramming during cellular stress responses.

  3. Stress, stress‐induced cortisol responses, and eyewitness identification performance

    PubMed Central

    Raymaekers, Linsey H.C.; Otgaar, Henry; Memon, Amina; Waltjen, Thijs T.; Nivo, Maud; Slegers, Chiel; Broers, Nick J.; Smeets, Tom

    2016-01-01

    Abstract In the eyewitness identification literature, stress and arousal at the time of encoding are considered to adversely influence identification performance. This assumption is in contrast with findings from the neurobiology field of learning and memory, showing that stress and stress hormones are critically involved in forming enduring memories. This discrepancy may be related to methodological differences between the two fields of research, such as the tendency for immediate testing or the use of very short (1–2 hours) retention intervals in eyewitness research, while neurobiology studies insert at least 24 hours. Other differences refer to the extent to which stress‐responsive systems (i.e., the hypothalamic–pituitary–adrenal axis) are stimulated effectively under laboratory conditions. The aim of the current study was to conduct an experiment that accounts for the contemporary state of knowledge in both fields. In all, 123 participants witnessed a live staged theft while being exposed to a laboratory stressor that reliably elicits autonomic and glucocorticoid stress responses or while performing a control task. Salivary cortisol levels were measured to control for the effectiveness of the stress induction. One week later, participants attempted to identify the thief from target‐present and target‐absent line‐ups. According to regression and receiver operating characteristic analyses, stress did not have robust detrimental effects on identification performance. Copyright © 2016 John Wiley & Sons, Ltd. © 2016 The Authors Behavioral Sciences & the Law Published by John Wiley & Sons Ltd PMID:27417874

  4. Comparative transcriptome analysis of grapevine in response to copper stress

    PubMed Central

    Leng, Xiangpeng; Jia, Haifeng; Sun, Xin; Shangguan, Lingfei; Mu, Qian; Wang, Baoju; Fang, Jinggui

    2015-01-01

    Grapevine is one of the most economically important and widely cultivated fruit crop worldwide. With the industrialization and the popular application of cupric fungicides in grape industry, copper stress and copper pollution are also the factors affecting grape production and berry and wine quality. Here, 3,843 transcripts were significantly differently expressed genes in response to Cu stress by RNA-seq, which included 1,892 up-regulated and 1,951 down-regulated transcripts. During this study we found many known and novel Cu-induced and -repressed genes. Biological analysis of grape samples were indicated that exogenous Cu can influence chlorophylls metabolism and photosynthetic activities of grapevine. Most ROS detoxification systems, including antioxidant enzyme, stress-related proteins and secondary metabolites were strongly induced. Concomitantly, abscisic acid functioned as a negative regulator in Cu stress, in opposite action to ethylene, auxin, jasmonic acid, and brassinolide. This study also identified a set of Cu stress specifically activated genes coding copper transporter, P1B-type ATPase, multidrug transporters. Overall, this work was carried out to gain insights into the copper-regulated and stress-responsive mechanisms in grapevine at transcriptome level. This research can also provide some genetic information that can help us in better vinery management and breeding Cu-resistant grape cultivars. PMID:26673527

  5. Genetic erosion impedes adaptive responses to stressful environments

    PubMed Central

    Bijlsma, R; Loeschcke, Volker

    2012-01-01

    Biodiversity is increasingly subjected to human-induced changes of the environment. To persist, populations continually have to adapt to these often stressful changes including pollution and climate change. Genetic erosion in small populations, owing to fragmentation of natural habitats, is expected to obstruct such adaptive responses: (i) genetic drift will cause a decrease in the level of adaptive genetic variation, thereby limiting evolutionary responses; (ii) inbreeding and the concomitant inbreeding depression will reduce individual fitness and, consequently, the tolerance of populations to environmental stress. Importantly, inbreeding generally increases the sensitivity of a population to stress, thereby increasing the amount of inbreeding depression. As adaptation to stress is most often accompanied by increased mortality (cost of selection), the increase in the ‘cost of inbreeding’ under stress is expected to severely hamper evolutionary adaptive processes. Inbreeding thus plays a pivotal role in this process and is expected to limit the probability of genetically eroded populations to successfully adapt to stressful environmental conditions. Consequently, the dynamics of small fragmented populations may differ considerably from large nonfragmented populations. The resilience of fragmented populations to changing and deteriorating environments is expected to be greatly decreased. Alleviating inbreeding depression, therefore, is crucial to ensure population persistence. PMID:25568035

  6. HDAC6 regulates sensitivity to cell death in response to stress and post-stress recovery.

    PubMed

    Ryu, Hyun-Wook; Won, Hye-Rim; Lee, Dong Hoon; Kwon, So Hee

    2017-01-23

    Histone deacetylase 6 (HDAC6) plays an important role in stress responses such as misfolded protein-induced aggresomes, autophagy, and stress granules. However, precisely how HDAC6 manages response during and after cellular stress remains largely unknown. This study aimed to investigate the effect of HDAC6 on various stress and post-stress recovery responses. We showed that HIF-1α protein levels were reduced in HDAC6 knockout (KO) MEFs compared to wild-type (WT) MEFs in hypoxia. Furthermore, under hypoxia, HIF-1α levels were also reduced following rescue with either a catalytically inactive or a ubiqiutin-binding mutant HDAC6. HDAC6 deacetylated and upregulated the stability of HIF-1α, leading to activation of HIF-1α function under hypoxia. Notably, both the deacetylase and ubiquitin-binding activities of HDAC6 contributed to HIF-1α stabilization, but only deacetylase activity was required for HIF-1α transcriptional activity. Suppression of HDAC6 enhanced the interaction between HIF-1α and HSP70 under hypoxic conditions. In addition to hypoxia, depletion of HDAC6 caused hypersensitivity to cell death during oxidative stress and post-stress recovery. However, HDAC6 depletion had no effect on cell death in response to heat shock or ionizing radiation. Overall, our data suggest that HDAC6 may serve as a critical stress regulator in response to different cellular stresses.

  7. Ezrin Inhibition Up-regulates Stress Response Gene Expression.

    PubMed

    Çelik, Haydar; Bulut, Gülay; Han, Jenny; Graham, Garrett T; Minas, Tsion Z; Conn, Erin J; Hong, Sung-Hyeok; Pauly, Gary T; Hayran, Mutlu; Li, Xin; Özdemirli, Metin; Ayhan, Ayşe; Rudek, Michelle A; Toretsky, Jeffrey A; Üren, Aykut

    2016-06-17

    Ezrin is a member of the ERM (ezrin/radixin/moesin) family of proteins that links cortical cytoskeleton to the plasma membrane. High expression of ezrin correlates with poor prognosis and metastasis in osteosarcoma. In this study, to uncover specific cellular responses evoked by ezrin inhibition that can be used as a specific pharmacodynamic marker(s), we profiled global gene expression in osteosarcoma cells after treatment with small molecule ezrin inhibitors, NSC305787 and NSC668394. We identified and validated several up-regulated integrated stress response genes including PTGS2, ATF3, DDIT3, DDIT4, TRIB3, and ATF4 as novel ezrin-regulated transcripts. Analysis of transcriptional response in skin and peripheral blood mononuclear cells from NSC305787-treated mice compared with a control group revealed that, among those genes, the stress gene DDIT4/REDD1 may be used as a surrogate pharmacodynamic marker of ezrin inhibitor compound activity. In addition, we validated the anti-metastatic effects of NSC305787 in reducing the incidence of lung metastasis in a genetically engineered mouse model of osteosarcoma and evaluated the pharmacokinetics of NSC305787 and NSC668394 in mice. In conclusion, our findings suggest that cytoplasmic ezrin, previously considered a dormant and inactive protein, has important functions in regulating gene expression that may result in down-regulation of stress response genes.

  8. Transcriptome Analysis of Spartina pectinata in Response to Freezing Stress

    PubMed Central

    Nah, Gyoungju; Lee, Moonsub; Kim, Do-Soon; Rayburn, A. Lane; Voigt, Thomas; Lee, D. K.

    2016-01-01

    Prairie cordgrass (Spartina pectinata), a perennial C4 grass native to the North American prairie, has several distinctive characteristics that potentially make it a model crop for production in stressful environments. However, little is known about the transcriptome dynamics of prairie cordgrass despite its unique freezing stress tolerance. Therefore, the purpose of this work was to explore the transcriptome dynamics of prairie cordgrass in response to freezing stress at -5°C for 5 min and 30 min. We used a RNA-sequencing method to assemble the S. pectinata leaf transcriptome and performed gene-expression profiling of the transcripts under freezing treatment. Six differentially expressed gene (DEG) groups were categorized from the profiling. In addition, two major consecutive orders of gene expression were observed in response to freezing; the first being the acute up-regulation of genes involved in plasma membrane modification, calcium-mediated signaling, proteasome-related proteins, and transcription regulators (e.g., MYB and WRKY). The follow-up and second response was of genes involved in encoding the putative anti-freezing protein and the previously known DNA and cell-damage-repair proteins. Moreover, we identified the genes involved in epigenetic regulation and circadian-clock expression. Our results indicate that freezing response in S. pectinata reflects dynamic changes in rapid-time duration, as well as in metabolic, transcriptional, post-translational, and epigenetic regulation. PMID:27032112

  9. Psychological stress during exercise: immunoendocrine and oxidative responses.

    PubMed

    Huang, Chun-Jung; Webb, Heather E; Evans, Ronald K; McCleod, Kelly A; Tangsilsat, Supatchara E; Kamimori, Gary H; Acevedo, Edmund O

    2010-12-01

    The purpose of this study was to examine the changes in catecholamines (epinephrine [EPI] and norepinephrine [NE]), interleukin-2 (IL-2) and a biomarker of oxidative stress (8-isoprostane) in healthy individuals who were exposed to a dual challenge (physical and psychological stress). Furthermore, this study also examined the possible relationships between catecholamines (NE and EPI) and 8-isoprostane and between IL-2 and 8-isoprostane following a combined physical and psychological challenge. Seven healthy male subjects completed two experimental conditions. The exercise-alone condition (EAC) consisted of cycling at 60% VO(2max) for 37 min, while the dual-stress condition (DSC) included 20 min of a mental challenge while cycling. DSC showed greater EPI and 8-isoprostane levels (significant condition by time interaction). NE and IL-2 revealed significant change across time in both conditions. In addition, following dual stress, EPI area-under-the-curve (AUC) demonstrated a positive correlation with NE AUC and IL-2 AUC. NE AUC was positively correlated with IL-2 AUC and peak 8-isoprostane, and peak IL-2 was positively correlated with peak 8-isoprostane in response to a dual stress. The potential explanation for elevated oxidative stress during dual stress may be through the effects of the release of catecholamines and IL-2. These findings may further provide the potential explanation that dual stress alters physiological homeostasis in many occupations including firefighting, military operations and law enforcement. A greater understanding of these responses to stress can assist in finding strategies (e.g. exercise training) to overcome the inherent psychobiological challenges associated with physically and mentally demanding professions.

  10. General stress response to conventional and laparoscopic cholecystectomy.

    PubMed Central

    Glaser, F; Sannwald, G A; Buhr, H J; Kuntz, C; Mayer, H; Klee, F; Herfarth, C

    1995-01-01

    OBJECTIVE: In many retrospective and prospective observational studies, laparoscopic cholecystectomy (LC) compares favorably with conventional cholecystectomy (CC), with respect to length of hospital stay, postoperative pain, and pulmonary function, indicating a diminished operative trauma. Comparison of laboratory findings (stress hormones, blood glucose, interleukins) are a possibility to objectify stress and tissue trauma of laparoscopic and conventional cholecystectomy. SUMMARY BACKGROUND DATA: Major body injury, surgical or accidental, evokes reproducible hormonal and immunologic responses. The magnitude of many of these changes essentially is proportional to the extent of the injury. METHODS: In a prospective study, biochemical stress parameters were measured in the blood of patients undergoing elective cholecystectomy because of symptomatic cholecystolithiasis. Patients with acute cholecystitis, pancreatitis, choledocholithiasis, or malignant disease were excluded. Values from 40 patients after LC and from 18 patients after CC were compared. Both groups had similar patient characteristics, baseline values, and perioperative care, except for deeper anesthesia during CC. RESULTS: On postoperative day 1, epinephrine (p = 0,05), norepinephrine (p = 0.02), and glucose (p = 0.02) responses were higher after CC. Two days postoperatively, norepinephrine remained higher after CC (p < 0.01). Interleukin-1 beta responses were higher during (p < 0.01) and 6 hours after CC (p = 0.03). Interleukin-6 responses were higher 6 hours (p = 0.03), 1 day (p = 0.02), and 2 days (p < 0.01) after CC. CONCLUSIONS: The results show significant lower values of intraoperatively and postoperatively measured epinephrine, norepinephrine, interleukin-1 beta, and interleukin-6 in patients with laparoscopic cholecystectomy, indicating a minor stress response and tissue trauma in this group of patients. The results correspond to the favorable results of most other trials evaluating clinical

  11. Characterization of the physiological stress response in lingcod

    USGS Publications Warehouse

    Milston, R.H.; Davis, M.W.; Parker, S.J.; Olla, B.L.; Clements, S.; Schreck, C.B.

    2006-01-01

    The goal of this study was to describe the duration and magnitude of the physiological stress response in lingcod Ophiodon elongatus after exposure to brief handling and sublethal air stressors. The response to these stressors was determined during a 24-h recovery period by measuring concentrations of plasma cortisol, lactate, glucose, sodium, and potassium. Lingcod were subjected to brief handling followed by either a 15-min or a 45-min air stressor in the laboratory. After the 15-min stressor, an increase in cortisol or glucose could not be detected until after 5 min of recovery. Peak concentrations were measured after 30 min for cortisol and after 60 min for glucose and lactate. Glucose and lactate had returned to basal levels after 12 h, whereas cortisol did not return to basal levels until after 24 h of recovery. Immediately following a 45-min air stressor, all measured parameters were significantly elevated over levels in prestressor control fish. Cortisol concentrations tended to increase and reached a measured peak after 8 h of recovery, whereas glucose and lactate reached a measured peak after 1 h of recovery. Cortisol and lactate returned to basal levels within 24 h. Glucose, however, remained elevated even after 24 h of recovery. Plasma ions initially increased during the first hour of recovery, and the concentrations then declined to a level below that measured in control fish for the remainder of the 24-h recovery period. In addition, we evaluated the effect of fish size on the stress response. There was no significant difference between the stress response of smaller (41-49-cm [total length] and larger (50-67-cm) lingcod after 45 min air exposure. In general, both the magnitude and duration of the primary and secondary stress responses in lingcod are comparable to those of salmonids. ?? Copyright by the American Fisheries Society 2006.

  12. Responses of Succulents to Plant Water Stress 1

    PubMed Central

    Hanscom, Zac; Ting, Irwin P.

    1978-01-01

    Experiments were performed to test the hypothesis that succulents “shift” their method of photosynthetic metabolism in response to environmental change. Our data showed that there were at least three different responses of succulents to plant water status. When plant water status of Portulacaria afra (L.) Jacq. was lowered either by withholding water or by irrigating with 2% NaCl, a change from C3-photosynthesis to Crassulacean acid metabolism (CAM) occurred. Fluctuation of titratable acidity and nocturnal CO2 uptake was induced in the stressed plants. Stressed Peperomia obtusifolia A. Dietr. plants showed a change from C3-photosynthesis to internal cycling of CO2. Acid fluctuation commenced in response to stress but exogenous CO2 uptake did not occur. Zygocactus truncatus Haworth plants showed a pattern of acid fluctuation and nocturnal CO2 uptake typical of CAM even when well irrigated. The cacti converted from CAM to an internal CO2 cycle similar to Peperomia when plants were water-stressed. Reverse phase gas exchange in succulents results in low water loss to carbon gain. Water is conserved and low levels of metabolic activity are maintained during drought periods by complete stomatal closure and continual fluctuation of organic acids. PMID:16660285

  13. Sleep Disturbance and Older Adults' Inflammatory Responses to Acute Stress

    PubMed Central

    Heffner, Kathi L.; Ng, H. Mei; Suhr, Julie A.; France, Christopher R.; Marshall, Gailen D.; Pigeon, Wilfred R.; Moynihan, Jan A.

    2013-01-01

    Objectives Poor sleep diminishes mental and physical health. The objective of this study was to examine associations between sleep disturbance and interleukin-6 (IL-6) responses to acute mental stress in older adults. Design Observational study of community-dwelling, healthy older adults. Setting Participants completed the study in a clinical research laboratory of a mid-sized university. Participants Generally healthy, community-dwelling men and women 50 years of age and older. Measurements IL-6 and negative affect at rest and following a series of challenging cognitive tests; sleep quality; depressive symptoms; perceived stress; loneliness. Results Participants categorized as poor sleepers based on Pittsburgh Sleep Quality Index scores had significantly larger IL-6 responses to the cognitive stressors compared to good sleepers. The association between poor sleep and heightened IL-6 response to acute stress was not explained by other psychosocial factors previously linked to immune dysregulation, including depressive symptoms, perceived stress, and loneliness. Conclusions Findings add to the growing evidence for poor sleep as an independent risk factor for poor mental and physical health. Older adults may be particularly vulnerable to effects of sleep disturbance due to significant age-related changes in both sleep and inflammatory regulation. PMID:22327621

  14. Acute psychological stress induces short-term variable immune response.

    PubMed

    Breen, Michael S; Beliakova-Bethell, Nadejda; Mujica-Parodi, Lilianne R; Carlson, Joshua M; Ensign, Wayne Y; Woelk, Christopher H; Rana, Brinda K

    2016-03-01

    In spite of advances in understanding the cross-talk between the peripheral immune system and the brain, the molecular mechanisms underlying the rapid adaptation of the immune system to an acute psychological stressor remain largely unknown. Conventional approaches to classify molecular factors mediating these responses have targeted relatively few biological measurements or explored cross-sectional study designs, and therefore have restricted characterization of stress-immune interactions. This exploratory study analyzed transcriptional profiles and flow cytometric data of peripheral blood leukocytes with physiological (endocrine, autonomic) measurements collected throughout the sequence of events leading up to, during, and after short-term exposure to physical danger in humans. Immediate immunomodulation to acute psychological stress was defined as a short-term selective up-regulation of natural killer (NK) cell-associated cytotoxic and IL-12 mediated signaling genes that correlated with increased cortisol, catecholamines and NK cells into the periphery. In parallel, we observed down-regulation of innate immune toll-like receptor genes and genes of the MyD88-dependent signaling pathway. Correcting gene expression for an influx of NK cells revealed a molecular signature specific to the adrenal cortex. Subsequently, focusing analyses on discrete groups of coordinately expressed genes (modules) throughout the time-series revealed immune stress responses in modules associated to immune/defense response, response to wounding, cytokine production, TCR signaling and NK cell cytotoxicity which differed between males and females. These results offer a spring-board for future research towards improved treatment of stress-related disease including the impact of stress on cardiovascular and autoimmune disorders, and identifies an immune mechanism by which vulnerabilities to these diseases may be gender-specific.

  15. Silver nanoparticles induce endoplasmatic reticulum stress response in zebrafish

    SciTech Connect

    Christen, Verena; Capelle, Martinus; Fent, Karl

    2013-10-15

    Silver nanoparticles (AgNPs) find increasing applications, and therefore humans and the environment are increasingly exposed to them. However, potential toxicological implications are not sufficiently known. Here we investigate effects of AgNPs (average size 120 nm) on zebrafish in vitro and in vivo, and compare them to human hepatoma cells (Huh7). AgNPs are incorporated in zebrafish liver cells (ZFL) and Huh7, and in zebrafish embryos. In ZFL cells AgNPs lead to induction of reactive oxygen species (ROS), endoplasmatic reticulum (ER) stress response, and TNF-α. Transcriptional alterations also occur in pro-apoptotic genes p53 and Bax. The transcriptional profile differed in ZFL and Huh7 cells. In ZFL cells, the ER stress marker BiP is induced, concomitant with the ER stress marker ATF-6 and spliced XBP-1 after 6 h and 24 h exposure to 0.5 g/L and 0.05 g/L AgNPs, respectively. This indicates the induction of different pathways of the ER stress response. Moreover, AgNPs induce TNF-α. In zebrafish embryos exposed to 0.01, 0.1, 1 and 5 mg/L AgNPs hatching was affected and morphological defects occurred at high concentrations. ER stress related gene transcripts BiP and Synv are significantly up-regulated after 24 h at 0.1 and 5 mg/L AgNPs. Furthermore, transcriptional alterations occurred in the pro-apoptotic genes Noxa and p21. The ER stress response was strong in ZFL cells and occurred in zebrafish embryos as well. Our data demonstrate for the first time that AgNPs lead to induction of ER stress in zebrafish. The induction of ER stress can have several consequences including the activation of apoptotic and inflammatory pathways. - Highlights: • Effects of silver nanoparticles (120 nm AgNPs) are investigated in zebrafish. • AgNPs induce all ER stress reponses in vitro in zebrafish liver cells. • AgNPs induce weak ER stress in zebrafish embryos. • AgNPs induce oxidative stress and transcripts of pro-apoptosis genes.

  16. Aneuploidy triggers a TFEB-mediated lysosomal stress response.

    PubMed

    Santaguida, Stefano; Amon, Angelika

    2015-01-01

    Aneuploidy, defined as an alteration in chromosome number that is not a multiple of the haploid complement, severely affects cellular physiology. Changes in chromosome number lead to imbalances in cellular protein composition, thus disrupting cellular processes and causing proteins to misfold and aggregate. We recently reported that in mammalian cells protein aggregates are readily encapsulated within autophagosomes but are not degraded by lysosomes. This leads to a lysosomal stress response in which the transcription factor TFEB induces expression of factors needed for macroautophagy-mediated protein degradation. Our studies uncover lysosomal degradation defects as a feature of the aneuploid state, and a role for the transcription factor TFEB in the response thereto.

  17. Stress-strain response of plastic waste mixed soil.

    PubMed

    Babu, G L Sivakumar; Chouksey, Sandeep Kumar

    2011-03-01

    Recycling plastic waste from water bottles has become one of the major challenges worldwide. The present study provides an approach for the use plastic waste as reinforcement material in soil. The experimental results in the form of stress-strain-pore water pressure response are presented. Based on experimental test results, it is observed that the strength of soil is improved and compressibility reduced significantly with addition of a small percentage of plastic waste to the soil. The use of the improvement in strength and compressibility response due to inclusion of plastic waste can be advantageously used in bearing capacity improvement and settlement reduction in the design of shallow foundations.

  18. Responses of women to orthostatic and exercise stresses

    NASA Technical Reports Server (NTRS)

    Hoffler, G. W.; Jackson, M. M.; Johnson, R. L.; Baker, J. T.; Tatro, D.

    1990-01-01

    The results are presented from a special physiological study of women at the Johnson Space Center in 1976 to 1977. Its purpose was to establish a large (98 subjects) database from normal working women. The data sets are medical historical, clinical, anthropometric, and stress response statistics useful for establishing medical criteria for selecting women astronauts. Stressors were lower body negative pressure and static standing (both orthostatic) and treadmill exercise (ergometric). Data shown are original individual values with analyses and subsets, and statistical summaries and correlations relating to human responses to microgravity. Similarities appear between the characteristics of women in this study and those of women astronauts currently flying in Shuttle crews.

  19. Abiotic stress responses in plant roots: a proteomics perspective

    PubMed Central

    Ghosh, Dipanjana; Xu, Jian

    2014-01-01

    Abiotic stress conditions adversely affect plant growth, resulting in significant decline in crop productivity. To mitigate and recover from the damaging effects of such adverse environmental conditions, plants have evolved various adaptive strategies at cellular and metabolic levels. Most of these strategies involve dynamic changes in protein abundance that can be best explored through proteomics. This review summarizes comparative proteomic studies conducted with roots of various plant species subjected to different abiotic stresses especially drought, salinity, flood, and cold. The main purpose of this article is to highlight and classify the protein level changes in abiotic stress response pathways specifically in plant roots. Shared as well as stressor-specific proteome signatures and adaptive mechanism(s) are simultaneously described. Such a comprehensive account will facilitate the design of genetic engineering strategies that enable the development of broad-spectrum abiotic stress-tolerant crops. PMID:24478786

  20. Integrated metabolomics for abiotic stress responses in plants.

    PubMed

    Nakabayashi, Ryo; Saito, Kazuki

    2015-04-01

    Plants are considered to biosynthesize specialized (traditionally called secondary) metabolites to adapt to environmental stresses such as biotic and abiotic stresses. The majority of specialized metabolites induced by abiotic stress characteristically exhibit antioxidative activity in vitro, but their function in vivo is largely yet to be experimentally confirmed. In this review, we highlight recent advances in the identification of the role of abiotic stress-responsive specialized metabolites with an emphasis on flavonoids. Integrated 'omics' analysis, centered on metabolomics with a series of plant resources differing in their flavonoid accumulation, showed experimentally that flavonoids play a major role in antioxidation in vivo. In addition, the results also suggest the role of flavonoids in the vacuole. To obtain more in-depth insights, chemical and biological challenges need to be addressed for the identification of unknown specialized metabolites and their in vivo functions.

  1. Sleep duration and cardiovascular responses to stress in undergraduate men.

    PubMed

    Mezick, Elizabeth J; Matthews, Karen A; Hall, Martica H; Richard Jennings, J; Kamarck, Thomas W

    2014-01-01

    Short sleep has been related to incident cardiovascular disease, but physiological mechanisms accounting for this relationship are largely unknown. This study examines sleep duration and cardiovascular stress responses in 79 healthy, young men. Sleep duration was assessed by wrist actigraphy for seven nights. Participants then completed a series of laboratory stress tasks while heart rate and blood pressure were monitored. Shorter total sleep time was related to a greater reduction in high-frequency heart rate variability during stress tasks, and to prolonged elevations in heart rate and diastolic pressure following tasks. Associations were independent of age, race, body mass index, caffeine intake, and smoking status. In sum, healthy young men with shorter actigraphy-assessed sleep exhibit less cardiac vagal activity, and poorer heart rate and diastolic blood pressure recovery, upon encountering stressful stimuli, than those with longer sleep.

  2. Stress-responsive microRNAs in Populus.

    PubMed

    Lu, Shanfa; Sun, Ying-Hsuan; Chiang, Vincent L

    2008-07-01

    MicroRNAs (miRNAs), a group of small non-coding RNAs, have recently become the subject of intense study. They are a class of post-transcriptional negative regulators playing vital roles in plant development and growth. However, little is known about their regulatory roles in the responses of trees to the stressful environments incurred over their long-term growth. Here, we report the cloning of small RNAs from abiotic stressed tissues of Populus trichocarpa (Ptc) and the identification of 68 putative miRNA sequences that can be classified into 27 families based on sequence homology. Among them, nine families are novel, increasing the number of the known Ptc-miRNA families from 33 to 42. A total of 346 targets was predicted for the cloned Ptc-miRNAs using penalty scores of response to cold, heat, salt, dehydration, and mechanical stresses. Microarray analysis of known Ptc-miRNAs identified 19 additional cold stress-responsive Ptc-miRNAs from 14 miRNA gene families. Interestingly, we found that individual miRNAs of a family responded differentially to stress, which suggests that the members of a family may have different functions. These results reveal possible roles for miRNAs in the regulatory networks associated with the long-term growth of tree species and provide useful information for developing trees with a greater level of stress resistance.

  3. Transcriptional regulation of the stress response by mTOR.

    PubMed

    Aramburu, Jose; Ortells, M Carmen; Tejedor, Sonia; Buxadé, Maria; López-Rodríguez, Cristina

    2014-07-01

    The kinase mammalian target of rapamycin (mTOR) is a central regulator of cell growth and proliferation that integrates inputs from growth factor receptors, nutrient availability, intracellular ATP (adenosine 5'-triphosphate), and a variety of stressors. Since early works in the mid-1990s uncovered the role of mTOR in stimulating protein translation, this kinase has emerged as a rather multifaceted regulator of numerous processes. Whereas mTOR is generally activated by growth- and proliferation-stimulating signals, its activity can be reduced and even suppressed when cells are exposed to a variety of stress conditions. However, cells can also adapt to stress while maintaining their growth capacity and mTOR function. Despite knowledge accumulated on how stress represses mTOR, less is known about mTOR influencing stress responses. In this review, we discuss the capability of mTOR, in particular mTOR complex 1 (mTORC1), to activate stress-responsive transcription factors, and we outline open questions for future investigation.

  4. Specificity in stress response: epidermal keratinocytes exhibit specialized UV-responsive signal transduction pathways.

    PubMed

    Adachi, Makoto; Gazel, Alix; Pintucci, Giuseppe; Shuck, Alyssa; Shifteh, Shiva; Ginsburg, Dov; Rao, Laxmi S; Kaneko, Takehiko; Freedberg, Irwin M; Tamaki, Kunihiko; Blumenberg, Miroslav

    2003-10-01

    UV light, a paradigmatic initiator of cell stress, invokes responses that include signal transduction, activation of transcription factors, and changes in gene expression. Consequently, in epidermal keratinocytes, its principal and frequent natural target, UV regulates transcription of a distinctive set of genes. Hypothesizing that UV activates distinctive epidermal signal transduction pathways, we compared the UV-responsive activation of the JNK and NFkappaB pathways in keratinocytes, with the activation of the same pathways by other agents and in other cell types. Using of inhibitors and antisense oligonucleotides, we found that in keratinocytes only UVB/UVC activate JNK, while in other cell types UVA, heat shock, and oxidative stress do as well. Keratinocytes express JNK-1 and JNK-3, which is unexpected because JNK-3 expression is considered brain-specific. In keratinocytes, ERK1, ERK2, and p38 are activated by growth factors, but not by UV. UVB/UVC in keratinocytes activates Elk1 and AP1 exclusively through the JNK pathway. JNKK1 is essential for UVB/UVC activation of JNK in keratinocytes in vitro and in human skin in vivo. In contrast, in HeLa cells, used as a control, crosstalk among signal transduction pathways allows considerable laxity. In parallel, UVB/UVC and TNFalpha activate the NFkappaB pathway via distinct mechanisms, as shown using antisense oligonucleotides targeted against IKKbeta, the active subunit of IKK. This implies a specific UVB/UVC responsive signal transduction pathway independent from other pathways. Our results suggest that in epidermal keratinocytes specific signal transduction pathways respond to UV light. Based on these findings, we propose that the UV light is not a genetic stress response inducer in these cells, but a specific agent to which epidermis developed highly specialized responses.

  5. Ethylene signaling and regulation in plant growth and stress responses.

    PubMed

    Wang, Feifei; Cui, Xiankui; Sun, Yue; Dong, Chun-Hai

    2013-07-01

    Gaseous phytohormone ethylene affects many aspects of plant growth and development. The ethylene signaling pathway starts when ethylene binds to its receptors. Since the cloning of the first ethylene receptor ETR1 from Arabidopsis, a large number of studies have steadily improved our understanding of the receptors and downstream components in ethylene signal transduction pathway. This article reviews the regulation of ethylene receptors, signal transduction, and the posttranscriptional modulation of downstream components. Functional roles and importance of the ethylene signaling components in plant growth and stress responses are also discussed. Cross-reactions of ethylene with auxin and other phytohormones in plant organ growth will be analyzed. The studies of ethylene signaling in plant growth, development, and stress responses in the past decade greatly advanced our knowledge of how plants respond to endogenous signals and environmental factors.

  6. Enhanced cortisol response to stress in children in autism.

    PubMed

    Spratt, Eve G; Nicholas, Joyce S; Brady, Kathleen T; Carpenter, Laura A; Hatcher, Charles R; Meekins, Kirk A; Furlanetto, Richard W; Charles, Jane M

    2012-01-01

    Children with Autism often show difficulties in adapting to change. Previous studies of cortisol, a neurobiologic stress hormone reflecting hypothalamic-pituitary-adrenal (HPA) axis activity, in children with autism have demonstrated variable results. This study measured cortisol levels in children with and without Autism: (1) at rest; (2) in a novel environment; and (3) in response to a blood draw stressor. A significantly higher serum cortisol response was found in the group of children with autism. Analysis showed significantly higher peak cortisol levels and prolonged duration and recovery of cortisol elevation following the blood-stick stressor in children with autism. This study suggests increased reactivity of the HPA axis to stress and novel stimuli in children with autism.

  7. Carotid baroreflex responsiveness in heat-stressed humans

    NASA Technical Reports Server (NTRS)

    Crandall, C. G.

    2000-01-01

    The effects of whole body heating on human baroreflex function are relatively unknown. The purpose of this project was to identify whether whole body heating reduces the maximal slope of the carotid baroreflex. In 12 subjects, carotid-vasomotor and carotid-cardiac baroreflex responsiveness were assessed in normothermia and during whole body heating. Whole body heating increased sublingual temperature (from 36.4 +/- 0.1 to 37.4 +/- 0.1 degrees C, P < 0.01) and increased heart rate (from 59 +/- 3 to 83 +/- 3 beats/min, P < 0. 01), whereas mean arterial blood pressure (MAP) was slightly decreased (from 88 +/- 2 to 83 +/- 2 mmHg, P < 0.01). Carotid-vasomotor and carotid-cardiac responsiveness were assessed by identifying the maximal gain of MAP and heart rate to R wave-triggered changes in carotid sinus transmural pressure. Whole body heating significantly decreased the responsiveness of the carotid-vasomotor baroreflex (from -0.20 +/- 0.02 to -0.13 +/- 0.02 mmHg/mmHg, P < 0.01) without altering the responsiveness of the carotid-cardiac baroreflex (from -0.40 +/- 0.05 to -0.36 +/- 0.02 beats x min(-1) x mmHg(-1), P = 0.21). Carotid-vasomotor and carotid-cardiac baroreflex curves were shifted downward and upward, respectively, to accommodate the decrease in blood pressure and increase in heart rate that accompanied the heat stress. Moreover, the operating point of the carotid-cardiac baroreflex was shifted closer to threshold (P = 0.02) by the heat stress. Reduced carotid-vasomotor baroreflex responsiveness, coupled with a reduction in the functional reserve for the carotid baroreflex to increase heart rate during a hypotensive challenge, may contribute to increased susceptibility to orthostatic intolerance during a heat stress.

  8. REM Sleep Rebound as an Adaptive Response to Stressful Situations

    PubMed Central

    Suchecki, Deborah; Tiba, Paula Ayako; Machado, Ricardo Borges

    2011-01-01

    Stress and sleep are related to each other in a bidirectional way. If on one hand poor or inadequate sleep exacerbates emotional, behavioral, and stress-related responses, on the other hand acute stress induces sleep rebound, most likely as a way to cope with the adverse stimuli. Chronic, as opposed to acute, stress impairs sleep and has been claimed to be one of the triggering factors of emotional-related sleep disorders, such as insomnia, depressive- and anxiety-disorders. These outcomes are dependent on individual psychobiological characteristics, conferring even more complexity to the stress-sleep relationship. Its neurobiology has only recently begun to be explored, through animal models, which are also valuable for the development of potential therapeutic agents and preventive actions. This review seeks to present data on the effects of stress on sleep and the different approaches used to study this relationship as well as possible neurobiological underpinnings and mechanisms involved. The results of numerous studies in humans and animals indicate that increased sleep, especially the rapid eye movement phase, following a stressful situation is an important adaptive behavior for recovery. However, this endogenous advantage appears to be impaired in human beings and rodent strains that exhibit high levels of anxiety and anxiety-like behavior. PMID:22485105

  9. Systemic corazonin signalling modulates stress responses and metabolism in Drosophila

    PubMed Central

    Kubrak, Olga I.; Lushchak, Oleh V.; Zandawala, Meet

    2016-01-01

    Stress triggers cellular and systemic reactions in organisms to restore homeostasis. For instance, metabolic stress, experienced during starvation, elicits a hormonal response that reallocates resources to enable food search and readjustment of physiology. Mammalian gonadotropin-releasing hormone (GnRH) and its insect orthologue, adipokinetic hormone (AKH), are known for their roles in modulating stress-related behaviour. Here we show that corazonin (Crz), a peptide homologous to AKH/GnRH, also alters stress physiology in Drosophila. The Crz receptor (CrzR) is expressed in salivary glands and adipocytes of the liver-like fat body, and CrzR knockdown targeted simultaneously to both these tissues increases the fly's resistance to starvation, desiccation and oxidative stress, reduces feeding, alters expression of transcripts of Drosophila insulin-like peptides (DILPs), and affects gene expression in the fat body. Furthermore, in starved flies, CrzR-knockdown increases circulating and stored carbohydrates. Thus, our findings indicate that elevated systemic Crz signalling during stress coordinates increased food intake and diminished energy stores to regain metabolic homeostasis. Our study suggests that an ancient stress-peptide in Urbilateria evolved to give rise to present-day GnRH, AKH and Crz signalling systems. PMID:27810969

  10. Adaptations in endocannabinoid signaling in response to repeated homotypic stress: a novel mechanism for stress habituation.

    PubMed

    Patel, Sachin; Hillard, Cecilia J

    2008-06-01

    Daily life stressors are a major environmental factor contributing to precipitation and exacerbation of mental illness. Animal models using repeated homotypic stress induce anxious and depressive phenotypes and are used to study the pathophysiology of affective disorders. Here we discuss data demonstrating that repeated homotypic stress produces temporally and anatomically distinct changes in endocannabinoid signaling components within stress-responsive brain regions. We also present evidence describing the neural and behavioral correlates of these adaptations in endocannabinoid signaling. These data support a role for endocannabinoid signaling in the central nervous system response to chronic, homotypic stress, and specifically in the process of stress-response habituation. The clinical implications of these findings for the pathophysiology and treatment of affective disorders are discussed.

  11. Aldehyde Dehydrogenases in Cellular Responses to Oxidative/electrophilic Stress

    PubMed Central

    Singh, Surendra; Brocker, Chad; Koppaka, Vindhya; Ying, Chen; Jackson, Brian; Matsumoto, Akiko; Thompson, David C.; Vasiliou, Vasilis

    2013-01-01

    Reactive oxygen species (ROS) are continuously generated within living systems and the inability to manage ROS load leads to elevated oxidative stress and cell damage. Oxidative stress is coupled to the oxidative degradation of lipid membranes, also known as lipid peroxidation. This process generates over 200 types of aldehydes, many of which are highly reactive and toxic. Aldehyde dehydrogenases (ALDHs) metabolize endogenous and exogenous aldehydes and thereby mitigate oxidative/electrophilic stress in prokaryotic and eukaryotic organisms. ALDHs are found throughout the evolutionary gamut, from single celled organisms to complex multicellular species. Not surprisingly, many ALDHs in evolutionarily distant, and seemingly unrelated, species perform similar functions, including protection against a variety of environmental stressors like dehydration and ultraviolet radiation. The ability to act as an ‘aldehyde scavenger’ during lipid peroxidation is another ostensibly universal ALDH function found across species. Up-regulation of ALDHs is a stress response in bacteria (environmental and chemical stress), plants (dehydration, salinity and oxidative stress), yeast (ethanol exposure and oxidative stress), Caenorhabditis elegans (lipid peroxidation) and mammals (oxidative stress and lipid peroxidation). Recent studies have also identified ALDH activity as an important feature of cancer stem cells. In these cells, ALDH expression helps abrogate oxidative stress and imparts resistance against chemotherapeutic agents such as oxazaphosphorine, taxane and platinum drugs. The ALDH superfamily represents a fundamentally important class of enzymes that significantly contributes to the management of electrophilic/oxidative stress within living systems. Mutations in various ALDHs are associated with a variety of pathological conditions in humans, underscoring the fundamental importance of these enzymes in physiological and pathological processes. PMID:23195683

  12. WRKY Transcription Factors: Molecular Regulation and Stress Responses in Plants

    PubMed Central

    Phukan, Ujjal J.; Jeena, Gajendra S.; Shukla, Rakesh K.

    2016-01-01

    Plants in their natural habitat have to face multiple stresses simultaneously. Evolutionary adaptation of developmental, physiological, and biochemical parameters give advantage over a single window of stress but not multiple. On the other hand transcription factors like WRKY can regulate diverse responses through a complicated network of genes. So molecular orchestration of WRKYs in plant may provide the most anticipated outcome of simultaneous multiple responses. Activation or repression through W-box and W-box like sequences is regulated at transcriptional, translational, and domain level. Because of the tight regulation involved in specific recognition and binding of WRKYs to downstream promoters, they have become promising candidate for crop improvement. Epigenetic, retrograde and proteasome mediated regulation enable WRKYs to attain the dynamic cellular homeostatic reprograming. Overexpression of several WRKYs face the paradox of having several beneficial affects but with some unwanted traits. These overexpression-associated undesirable phenotypes need to be identified and removed for proper growth, development and yeild. Taken together, we have highlighted the diverse regulation and multiple stress response of WRKYs in plants along with the future prospects in this field of research. PMID:27375634

  13. MOF maintains transcriptional programs regulating cellular stress response.

    PubMed

    Sheikh, B N; Bechtel-Walz, W; Lucci, J; Karpiuk, O; Hild, I; Hartleben, B; Vornweg, J; Helmstädter, M; Sahyoun, A H; Bhardwaj, V; Stehle, T; Diehl, S; Kretz, O; Voss, A K; Thomas, T; Manke, T; Huber, T B; Akhtar, A

    2016-05-01

    MOF (MYST1, KAT8) is the major H4K16 lysine acetyltransferase (KAT) in Drosophila and mammals and is essential for embryonic development. However, little is known regarding the role of MOF in specific cell lineages. Here we analyze the differential role of MOF in proliferating and terminally differentiated tissues at steady state and under stress conditions. In proliferating cells, MOF directly binds and maintains the expression of genes required for cell cycle progression. In contrast, MOF is dispensable for terminally differentiated, postmitotic glomerular podocytes under physiological conditions. However, in response to injury, MOF is absolutely critical for podocyte maintenance in vivo. Consistently, we detect defective nuclear, endoplasmic reticulum and Golgi structures, as well as presence of multivesicular bodies in vivo in podocytes lacking Mof following injury. Undertaking genome-wide expression analysis of podocytes, we uncover several MOF-regulated pathways required for stress response. We find that MOF, along with the members of the non-specific lethal but not the male-specific lethal complex, directly binds to genes encoding the lysosome, endocytosis and vacuole pathways, which are known regulators of podocyte maintenance. Thus, our work identifies MOF as a key regulator of cellular stress response in glomerular podocytes.

  14. Gender affects sympathetic and hemodynamic response to postural stress

    NASA Technical Reports Server (NTRS)

    Shoemaker, J. K.; Hogeman, C. S.; Khan, M.; Kimmerly, D. S.; Sinoway, L. I.

    2001-01-01

    We tested the hypothesis that differences in sympathetic reflex responses to head-up tilt (HUT) between males (n = 9) and females (n = 8) were associated with decrements in postural vasomotor responses in women. Muscle sympathetic nerve activity (MSNA; microneurography), heart rate, stroke volume (SV; Doppler), and blood pressure (Finapres) were measured during a progressive HUT protocol (5 min at each of supine, 20 degrees, 40 degrees, and 60 degrees ). MSNA and hemodynamic responses were also measured during the cold pressor test (CPT) to examine nonbaroreflex neurovascular control. SV was normalized to body surface area (SV(i)) to calculate the index of cardiac output (Q(i)), and total peripheral resistance (TPR). During HUT, heart rate increased more in females versus males (P < 0.001) and SV(i) and Q(i) decreased similarly in both groups. Mean arterial pressure (MAP) increased to a lesser extent in females versus males in the HUT (P < 0.01) but increases in TPR during HUT were similar. MSNA burst frequency was lower in females versus males in supine (P < 0.03) but increased similarly during HUT. Average amplitude/burst increased in 60 degrees HUT for males but not females. Both males and females demonstrated an increase in MAP as well as MSNA burst frequency, mean burst amplitude, and total MSNA during the CPT. However, compared with females, males demonstrated a greater neural response (DeltaTotal MSNA) due to a larger increase in mean burst amplitude (P < 0.05). Therefore, these data point to gender-specific autonomic responses to cardiovascular stress. The different MSNA response to postural stress between genders may contribute importantly to decrements in blood pressure control during HUT in females.

  15. Stress responses of human dermal fibroblasts exposed to zinc pyrithione.

    PubMed

    Rudolf, Emil; Cervinka, Miroslav

    2011-07-28

    Zinc pyrithione is used as a topical agent in a range of medicinal and cosmetic applications. Despite its extensive use and reported beneficial effects in treatment of various dermal problems, its potential toxicity towards skin cells remains relatively underexplored. In this work we investigated effects of nM zinc pyrithione on cell stress response pathways of primary human skin fibroblasts during 24h of exposure. We demonstrate that zinc pyrithione-induced cytotoxity in dermal fibroblasts is dose-dependent and it associates with increased intracellular zinc concentrations and activated stress response pathways including p53 and stress kinase p38. Higher zinc pyrithione concentrations (500nM and above) stimulate oxidative stress and moderate DNA damage which occur in the presence of activated p38 kinase. Cells further upregulate the expression of p53 which increases its transcriptional activity while mitogenic signaling exemplified by mTOR (mammalian target of rapamycin) expression is suppressed and these steps lead to mitochondrial, caspase-dependent apoptosis. Conversely, lower zinc concentrations (125nM) fail to induce oxidative stress and significant DNA damage; however, treated cells still activate p38 and upregulate the expression and transcriptional activity of p53 and its target gene p21 as well as the expression of p16 in the presence of active mTOR pathway and a changed DNA methylation pattern. The end result is premature senescence phenotype. Specific pharmacological inhibitors as well as gene knockdown technology prove that an interaction between p38, p53 and mTOR might be responsible for these observed endpoints. Taken together, exposure of dermal fibroblasts to varying concentrations of zinc pyrithione may result in either cell death-apoptosis or cellular premature senescence which attests to the ability of this compound to affect this type of cells in an in vitro model system.

  16. Understanding the adaptive response in vertebrates: the phenomenon of ease and ease response during post-stress acclimation.

    PubMed

    Subhash Peter, M C

    2013-01-15

    Vertebrates have evolved mechanisms to perceive stressors that arise either from their body or from the environment. Consequently, a state of stress and stress response occur in fish which is characterized by a disturbed physiological homeostasis. The pattern of stress response becomes complex as a result of neuroendocrine involvement and shows varied magnitudes in fishes depending on the nature and the severity of stressors. The integrated and compensatory physiological modifications in fishes during their early phase of adaptive response favor them to accommodate the imposed stressor through the process of stress acclimation. In contrast, with the direction of neuroendocrine signals, a phase of recovery often called post-stress acclimation occurs if the animal gets away from the stressor exposure. During this late phase of adaptive response, physiological modifications operate in favor of the animal that reduces the magnitude of stress response and finally to a phase of normality as animals possess the urge to correct its disrupted homeostasis. The phenomenon of ease and its response thus reduces the allostatic load, resets the homeostatic state through physiologic processes and corrects the stress-induced homeostatic disturbance with the aid of neuroendocrine signals. Ample evidences are now available to support this novel concept of ease and ease response where mitigation of the intensity of stress response occurs physiologically. Treatment of fish with melatonin or serotonin precursor tryptophan can modify the magnitude of stress response as evident in the pattern of tested physiological indices. In addition to cortisol, thyroid hormone as a major stress modifier hormone is involved in the regulation of ease response in fish probably due to the mechanisms involving inter-hormonal interference. Understanding the mechanisms of adaptive responses in vertebrates thus warranties more studies on the physiology of ease and its response.

  17. Oxidative stress and antioxidant response in a thermotolerant yeast.

    PubMed

    Mejía-Barajas, Jorge A; Montoya-Pérez, Rocío; Salgado-Garciglia, Rafael; Aguilera-Aguirre, Leopoldo; Cortés-Rojo, Christian; Mejía-Zepeda, Ricardo; Arellano-Plaza, Melchor; Saavedra-Molina, Alfredo

    Stress tolerance is a key attribute that must be considered when using yeast cells for industrial applications. High temperature is one factor that can cause stress in yeast. High environmental temperature in particular may exert a natural selection pressure to evolve yeasts into thermotolerant strains. In the present study, three yeasts (Saccharomyces cerevisiae, MC4, and Kluyveromyces marxianus, OFF1 and SLP1) isolated from hot environments were exposed to increased temperatures and were then compared with a laboratory yeast strain. Their resistance to high temperature, oxidative stress, and antioxidant response were evaluated, along with the fatty acid composition of their cell membranes. The SLP1 strain showed a higher specific growth rate, biomass yield, and biomass volumetric productivity while also showing lower duplication time, reactive oxygen species (ROS) production, and lipid peroxidation. In addition, the SLP1 strain demonstrated more catalase activity after temperature was increased, and this strain also showed membranes enriched in saturated fatty acids. It is concluded that the SLP1 yeast strain is a thermotolerant yeast with less oxidative stress and a greater antioxidant response. Therefore, this strain could be used for fermentation at high temperatures.

  18. Peripheral vascular responses to heat stress after hindlimb suspension

    NASA Technical Reports Server (NTRS)

    Looft-Wilson, Robin C.; Gisolfi, Carl V.

    2002-01-01

    PURPOSE: The purpose of this study was to determine whether hindlimb suspension (which simulates the effects of microgravity) results in impaired hemodynamic responses to heat stress or alterations in mesenteric small artery sympathetic nerve innervation. METHODS: Over 28 d, 16 male Sprague-Dawley rats were hindlimb-suspended, and 13 control rats were housed in the same type of cage. After the treatment, mean arterial pressure (MAP), colonic temperature (Tcol), and superior mesenteric and iliac artery resistances (using Doppler flowmetry) were measured during heat stress [exposure to 42 degrees C until the endpoint of 80 mm Hg blood pressure was reached (75 +/- 9 min); endpoint Tcore = 43.6 +/- 0.2] while rats were anesthetized (sodium pentobarbital, 50 mg x kg(-1) BW). RESULTS: Hindlimb-suspended and control rats exhibited similar increases in Tcol, MAP, and superior mesenteric artery resistance, and similar decreases in iliac resistance during heat stress (endpoint was a fall in MAP below 80 mm Hg). Tyrosine hydroxylase immunostaining indicated similar sympathetic nerve innervation in small mesenteric arteries from both groups. CONCLUSION: Hindlimb suspension does not alter the hemodynamic or thermoregulatory responses to heat stress in the anesthetized rat or mesenteric sympathetic nerve innervation, suggesting that this sympathetic pathway is intact.

  19. Flavivirus Infection Uncouples Translation Suppression from Cellular Stress Responses

    PubMed Central

    Roth, Hanna; Magg, Vera; Uch, Fabian; Mutz, Pascal; Klein, Philipp; Haneke, Katharina; Lohmann, Volker; Bartenschlager, Ralf; Fackler, Oliver T.; Locker, Nicolas; Stoecklin, Georg

    2017-01-01

    ABSTRACT As obligate parasites, viruses strictly depend on host cell translation for the production of new progeny, yet infected cells also synthesize antiviral proteins to limit virus infection. Modulation of host cell translation therefore represents a frequent strategy by which viruses optimize their replication and spread. Here we sought to define how host cell translation is regulated during infection of human cells with dengue virus (DENV) and Zika virus (ZIKV), two positive-strand RNA flaviviruses. Polysome profiling and analysis of de novo protein synthesis revealed that flavivirus infection causes potent repression of host cell translation, while synthesis of viral proteins remains efficient. Selective repression of host cell translation was mediated by the DENV polyprotein at the level of translation initiation. In addition, DENV and ZIKV infection suppressed host cell stress responses such as the formation of stress granules and phosphorylation of the translation initiation factor eIF2α (α subunit of eukaryotic initiation factor 2). Mechanistic analyses revealed that translation repression was uncoupled from the disruption of stress granule formation and eIF2α signaling. Rather, DENV infection induced p38-Mnk1 signaling that resulted in the phosphorylation of the eukaryotic translation initiation factor eIF4E and was essential for the efficient production of virus particles. Together, these results identify the uncoupling of translation suppression from the cellular stress responses as a conserved strategy by which flaviviruses ensure efficient replication in human cells. PMID:28074025

  20. Roles of horseradish peroxidase in response to terbium stress.

    PubMed

    Zhang, Xuanbo; Wang, Lihong; Zhou, Qing

    2014-10-01

    The pollution of the environment by rare earth elements (REEs) causes deleterious effects on plants. Peroxidase plays important roles in plant response to various environmental stresses. Here, to further understand the overall roles of peroxidase in response to REE stress, the effects of the REE terbium ion (Tb(3+)) on the peroxidase activity and H2O2 and lignin contents in the leaves and roots of horseradish during different growth stages were simultaneously investigated. The results showed that after 24 and 48 h of Tb(3+) treatment, the peroxidase activity in horseradish leaves decreased, while the H2O2 and lignin contents increased. After a long-term (8 and 16 days) treatment with Tb(3+), these effects were also observed in the roots. The analysis of the changes in peroxidase activity and H2O2 and lignin contents revealed that peroxidase plays important roles in not only reactive oxygen species scavenging but also cell wall lignification in horseradish under Tb(3+) stress. These roles were closely related to the dose of Tb(3+), duration of stress, and growth stages of horseradish.

  1. Convergent Induction of Osmotic Stress-Responses 1

    PubMed Central

    Thomas, John C.; McElwain, Elizabeth F.; Bohnert, Hans J.

    1992-01-01

    In Mesembryanthemum crystallinum, salt stress induces the accumulation of proline and a specific isoform of the enzyme phosphoenolpyruvate carboxylase (PEPCase) prior to the switch from C3 to Crassulacean acid metabolism (CAM). To determine whether plant growth regulators initiate or imitate these responses, we have compared the effects elicited by NaCl, abscisic acid (ABA), and cytokinins using PEPCase and proline levels as diagnostic tools. Exogenously applied ABA is a poor substitute for NaCl in inducing proline and CAM-specific PEPCase accumulation. Even though ABA levels increase 8- to 10-fold in leaves during salt stress, inhibition of ABA accumulation does not affect these salt-induced responses. In contrast, the addition of cytokinins (6-benzylaminopurine, zeatin, 2-isopentyladenine) mimic salt by greatly increasing proline and PEPCase amounts. Endogenous zeatin levels remain unchanged during salt stress. We conclude: (a) The salt-induced accumulation of proline and PEPCase is coincident with, but is not attributable to, the rise in ABA or zeatin concentration. (b) For the first time, cytokinins and NaCl are implicated as independent initiators of a sensing pathway that signals leaves to alter PEPCase gene expression. (c) During stress, the sensing of osmotic imbalances leading to ABA, proline, and CAM-specific PEPCase accumulation may be mediated directly by NaCl. Images Figure 1 Figure 3 Figure 4 Figure 5 Figure 7 PMID:16652978

  2. Circadian control of β-cell function and stress responses.

    PubMed

    Lee, J; Liu, R; de Jesus, D; Kim, B S; Ma, K; Moulik, M; Yechoor, V

    2015-09-01

    Circadian disruption is the bane of modern existence and its deleterious effects on health; in particular, diabetes and metabolic syndrome have been well recognized in shift workers. Recent human studies strongly implicate a 'dose-dependent' relationship between circadian disruption and diabetes. Genetic and environmental disruption of the circadian clock in rodents leads to diabetes secondary to β-cell failure. Deletion of Bmal1, a non-redundant core clock gene, leads to defects in β-cell stimulus-secretion coupling, decreased glucose-stimulated ATP production, uncoupling of OXPHOS and impaired glucose-stimulated insulin secretion. Both genetic and environmental circadian disruptions are sufficient to induce oxidative stress and this is mediated by a disruption of the direct transcriptional control of the core molecular clock and Bmal1 on Nrf2, the master antioxidant transcription factor in the β-cell. In addition, circadian disruption also leads to a dysregulation of the unfolded protein response and leads to endoplasmic reticulum stress in β-cells. Both the oxidative and endoplasmic reticulum (ER) stress contribute to an impairment of mitochondrial function and β-cell failure. Understanding the basis of the circadian control of these adaptive stress responses offers hope to target them for pharmacological modulation to prevent and mitigate the deleterious metabolic consequences of circadian disruption.

  3. Gene Expression Dynamics Accompanying the Sponge Thermal Stress Response

    PubMed Central

    Guzman, Christine; Conaco, Cecilia

    2016-01-01

    Marine sponges are important members of coral reef ecosystems. Thus, their responses to changes in ocean chemistry and environmental conditions, particularly to higher seawater temperatures, will have potential impacts on the future of these reefs. To better understand the sponge thermal stress response, we investigated gene expression dynamics in the shallow water sponge, Haliclona tubifera (order Haplosclerida, class Demospongiae), subjected to elevated temperature. Using high-throughput transcriptome sequencing, we show that these conditions result in the activation of various processes that interact to maintain cellular homeostasis. Short-term thermal stress resulted in the induction of heat shock proteins, antioxidants, and genes involved in signal transduction and innate immunity pathways. Prolonged exposure to thermal stress affected the expression of genes involved in cellular damage repair, apoptosis, signaling and transcription. Interestingly, exposure to sublethal temperatures may improve the ability of the sponge to mitigate cellular damage under more extreme stress conditions. These insights into the potential mechanisms of adaptation and resilience of sponges contribute to a better understanding of sponge conservation status and the prediction of ecosystem trajectories under future climate conditions. PMID:27788197

  4. Oxidative stress contributes to autophagy induction in response to endoplasmic reticulum stress in Chlamydomonas reinhardtii.

    PubMed

    Pérez-Martín, Marta; Pérez-Pérez, María Esther; Lemaire, Stéphane D; Crespo, José L

    2014-10-01

    The accumulation of unfolded/misfolded proteins in the endoplasmic reticulum (ER) results in the activation of stress responses, such as the unfolded protein response or the catabolic process of autophagy to ultimately recover cellular homeostasis. ER stress also promotes the production of reactive oxygen species, which play an important role in autophagy regulation. However, it remains unknown whether reactive oxygen species are involved in ER stress-induced autophagy. In this study, we provide evidence connecting redox imbalance caused by ER stress and autophagy activation in the model unicellular green alga Chlamydomonas reinhardtii. Treatment of C. reinhardtii cells with the ER stressors tunicamycin or dithiothreitol resulted in up-regulation of the expression of genes encoding ER resident endoplasmic reticulum oxidoreductin1 oxidoreductase and protein disulfide isomerases. ER stress also triggered autophagy in C. reinhardtii based on the protein abundance, lipidation, cellular distribution, and mRNA levels of the autophagy marker ATG8. Moreover, increases in the oxidation of the glutathione pool and the expression of oxidative stress-related genes were detected in tunicamycin-treated cells. Our results revealed that the antioxidant glutathione partially suppressed ER stress-induced autophagy and decreased the toxicity of tunicamycin, suggesting that oxidative stress participates in the control of autophagy in response to ER stress in C. reinhardtii In close agreement, we also found that autophagy activation by tunicamycin was more pronounced in the C. reinhardtii sor1 mutant, which shows increased expression of oxidative stress-related genes.

  5. The transcriptional regulatory network in the drought response and its crosstalk in abiotic stress responses including drought, cold, and heat

    PubMed Central

    Nakashima, Kazuo; Yamaguchi-Shinozaki, Kazuko; Shinozaki, Kazuo

    2014-01-01

    Drought negatively impacts plant growth and the productivity of crops around the world. Understanding the molecular mechanisms in the drought response is important for improvement of drought tolerance using molecular techniques. In plants, abscisic acid (ABA) is accumulated under osmotic stress conditions caused by drought, and has a key role in stress responses and tolerance. Comprehensive molecular analyses have shown that ABA regulates the expression of many genes under osmotic stress conditions, and the ABA-responsive element (ABRE) is the major cis-element for ABA-responsive gene expression. Transcription factors (TFs) are master regulators of gene expression. ABRE-binding protein and ABRE-binding factor TFs control gene expression in an ABA-dependent manner. SNF1-related protein kinases 2, group A 2C-type protein phosphatases, and ABA receptors were shown to control the ABA signaling pathway. ABA-independent signaling pathways such as dehydration-responsive element-binding protein TFs and NAC TFs are also involved in stress responses including drought, heat, and cold. Recent studies have suggested that there are interactions between the major ABA signaling pathway and other signaling factors in stress responses. The important roles of these TFs in crosstalk among abiotic stress responses will be discussed. Control of ABA or stress signaling factor expression can improve tolerance to environmental stresses. Recent studies using crops have shown that stress-specific overexpression of TFs improves drought tolerance and grain yield compared with controls in the field. PMID:24904597

  6. Dose response relationship in anti-stress gene regulatory networks.

    PubMed

    Zhang, Qiang; Andersen, Melvin E

    2007-03-02

    To maintain a stable intracellular environment, cells utilize complex and specialized defense systems against a variety of external perturbations, such as electrophilic stress, heat shock, and hypoxia, etc. Irrespective of the type of stress, many adaptive mechanisms contributing to cellular homeostasis appear to operate through gene regulatory networks that are organized into negative feedback loops. In general, the degree of deviation of the controlled variables, such as electrophiles, misfolded proteins, and O2, is first detected by specialized sensor molecules, then the signal is transduced to specific transcription factors. Transcription factors can regulate the expression of a suite of anti-stress genes, many of which encode enzymes functioning to counteract the perturbed variables. The objective of this study was to explore, using control theory and computational approaches, the theoretical basis that underlies the steady-state dose response relationship between cellular stressors and intracellular biochemical species (controlled variables, transcription factors, and gene products) in these gene regulatory networks. Our work indicated that the shape of dose response curves (linear, superlinear, or sublinear) depends on changes in the specific values of local response coefficients (gains) distributed in the feedback loop. Multimerization of anti-stress enzymes and transcription factors into homodimers, homotrimers, or even higher-order multimers, play a significant role in maintaining robust homeostasis. Moreover, our simulation noted that dose response curves for the controlled variables can transition sequentially through four distinct phases as stressor level increases: initial superlinear with lesser control, superlinear more highly controlled, linear uncontrolled, and sublinear catastrophic. Each phase relies on specific gain-changing events that come into play as stressor level increases. The low-dose region is intrinsically nonlinear, and depending on

  7. Extensive Translatome Remodeling during ER Stress Response in Mammalian Cells

    PubMed Central

    Ventoso, Iván; Kochetov, Alex; Montaner, David; Dopazo, Joaquín; Santoyo, Javier

    2012-01-01

    In this work we have described the translatome of two mammalian cell lines, NIH3T3 and Jurkat, by scoring the relative polysome association of ∼10,000 mRNA under normal and ER stress conditions. We have found that translation efficiencies of mRNA correlated poorly with transcript abundance, although a general tendency was observed so that the highest translation efficiencies were found in abundant mRNA. Despite the differences found between mouse (NIH3T3) and human (Jurkat) cells, both cell types share a common translatome composed by ∼800–900 mRNA that encode proteins involved in basic cellular functions. Upon stress, an extensive remodeling in translatomes was observed so that translation of ∼50% of mRNA was inhibited in both cell types, this effect being more dramatic for those mRNA that accounted for most of the cell translation. Interestingly, we found two subsets comprising 1000–1500 mRNA whose translation resisted or was induced by stress. Translation arrest resistant class includes many mRNA encoding aminoacyl tRNA synthetases, ATPases and enzymes involved in DNA replication and stress response such as BiP. This class of mRNA is characterized by high translation rates in both control and stress conditions. Translation inducible class includes mRNA whose translation was relieved after stress, showing a high enrichment in early response transcription factors of bZIP and zinc finger C2H2 classes. Unlike yeast, a general coordination between changes in translation and transcription upon stress (potentiation) was not observed in mammalian cells. Among the different features of mRNA analyzed, we found a relevant association of translation efficiency with the presence of upstream ATG in the 5′UTR and with the length of coding sequence of mRNA, and a looser association with other parameters such as the length and the G+C content of 5′UTR. A model for translatome remodeling during the acute phase of stress response in mammalian cells is proposed. PMID

  8. Cotranslational response to proteotoxic stress by elongation pausing of ribosomes.

    PubMed

    Liu, Botao; Han, Yan; Qian, Shu-Bing

    2013-02-07

    Translational control permits cells to respond swiftly to a changing environment. Rapid attenuation of global protein synthesis under stress conditions has been largely ascribed to the inhibition of translation initiation. Here we report that intracellular proteotoxic stress reduces global protein synthesis by halting ribosomes on transcripts during elongation. Deep sequencing of ribosome-protected messenger RNA (mRNA) fragments reveals an early elongation pausing, roughly at the site where nascent polypeptide chains emerge from the ribosomal exit tunnel. Inhibiting endogenous chaperone molecules by a dominant-negative mutant or chemical inhibitors recapitulates the early elongation pausing, suggesting a dual role of molecular chaperones in facilitating polypeptide elongation and cotranslational folding. Our results further support the chaperone "trapping" mechanism in promoting the passage of nascent chains. Our study reveals that translating ribosomes fine tune the elongation rate by sensing the intracellular folding environment. The early elongation pausing represents a cotranslational stress response to maintain the intracellular protein homeostasis.

  9. Responses of Yeast Biocontrol Agents to Environmental Stress

    PubMed Central

    Sui, Yuan; Wisniewski, Michael; Droby, Samir

    2015-01-01

    Biological control of postharvest diseases, utilizing wild species and strains of antagonistic yeast species, is a research topic that has received considerable attention in the literature over the past 30 years. In principle, it represents a promising alternative to chemical fungicides for the management of postharvest decay of fruits, vegetables, and grains. A yeast-based biocontrol system is composed of a tritrophic interaction between a host (commodity), a pathogen, and a yeast species, all of which are affected by environmental factors such as temperature, pH, and UV light as well as osmotic and oxidative stresses. Additionally, during the production process, biocontrol agents encounter various severe abiotic stresses that also impact their viability. Therefore, understanding the ecological fitness of the potential yeast biocontrol agents and developing strategies to enhance their stress tolerance are essential to their efficacy and commercial application. The current review provides an overview of the responses of antagonistic yeast species to various environmental stresses, the methods that can be used to improve stress tolerance and efficacy, and the related mechanisms associated with improved stress tolerance. PMID:25710368

  10. Low-stress and high-stress singing have contrasting effects on glucocorticoid response

    PubMed Central

    Fancourt, Daisy; Aufegger, Lisa; Williamon, Aaron

    2015-01-01

    Performing music in public is widely recognized as a potentially stress-inducing activity. However, despite the interest in music performance as an acute psychosocial stressor, there has been relatively little research on the effects of public performance on the endocrine system. This study examined the impact of singing in a low-stress performance situation and a high-stress live concert on levels of glucocorticoids (cortisol and cortisone) in 15 professional singers. The results showed a significant decrease in both cortisol and cortisone across the low-stress condition, suggesting that singing in itself is a stress-reducing (and possibly health-promoting) activity, but significant increases across the high-stress condition. This is the first study to demonstrate that singing affects cortisol as well as cortisone responses and that these responses are modulated by the conditions of performance. PMID:26388794

  11. Biology and therapy of fibromyalgia. Stress, the stress response system, and fibromyalgia

    PubMed Central

    Martinez-Lavin, Manuel

    2007-01-01

    Stress is a state of disharmony, or threatened homeostasis. A stressor could have a psychological origin or a biological origin. Societies have become more intricate with industrialization, and modern individuals try to adapt to the new defiance by forcing their stress response system. The main component of the stress response network is the autonomic nervous system. The present article reviews current knowledge on autonomic dysfunction in fibromyalgia. Sympathetic hyperactivity has been consistently described by diverse groups of investigators. Fibromyalgia is proposed to be a sympathetically maintained neuropathic pain syndrome, and genomic data support this contention. Autonomic dysfunction may also explain other fibromyalgia features not related to pain. PMID:17626613

  12. The Unfolded Protein Response Supports Plant Development and Defense as well as Responses to Abiotic Stress

    PubMed Central

    Bao, Yan; Howell, Stephen H.

    2017-01-01

    The unfolded protein response (UPR) is a stress response conserved in eukaryotic organisms and activated by the accumulation of misfolded proteins in the endoplasmic reticulum (ER). Adverse environmental conditions disrupt protein folding in the ER and trigger the UPR. Recently, it was found that the UPR can be elicited in the course of plant development and defense. During vegetative plant development, the UPR is involved in normal root growth and development, the effect of which can be largely attributed to the influence of the UPR on plant hormone biology. The UPR also functions in plant reproductive development by protecting male gametophyte development from heat stress. In terms of defense, the UPR has been implicated in virus and microbial defense. Viral defense represents a double edge sword in that various virus infections activate the UPR, however, in a number of cases, the UPR actually supports viral infections. The UPR also plays a role in plant immunity to bacterial infections, again through the action of plant hormones in regulating basal immunity responses. PMID:28360918

  13. Is pressure stressful? The impact of pressure on the stress response and category learning.

    PubMed

    McCoy, Shannon K; Hutchinson, Steven; Hawthorne, Lauren; Cosley, Brandon J; Ell, Shawn W

    2014-06-01

    We examined the basic question of whether pressure is stressful. We proposed that when examining the role of stress or pressure in cognitive performance, it is important to consider the type of pressure, the stress response, and the aspect of cognition assessed. In Experiment 1, outcome pressure was not experienced as stressful but did lead to impaired performance on a rule-based (RB) category-learning task, but not on a more procedural information-integration (II) task. In Experiment 2, the addition of monitoring pressure resulted in a modest stress response to combined pressure and impairment on both tasks. Across experiments, higher stress appraisals were associated with decreased performance on the RB, but not on the II, task. In turn, higher stress reactivity (i.e., heart rate) was associated with enhanced performance on the II, but not on the RB, task. This work represents an initial step toward integrating the stress cognition and pressure cognition literatures and suggests that integrating these fields may require consideration of the type of pressure, the stress response, and the cognitive system mediating performance.

  14. Autonomic mechanisms underpinning the stress response in borderline hypertensive rats

    PubMed Central

    Šarenac, Olivera; Lozić, Maja; Drakulić, Srdja; Bajić, Dragana; Paton, Julian F; Murphy, David; Japundžić-Žigon, Nina

    2011-01-01

    This study investigates blood pressure (BP) and heart rate (HR) short-term variability and spontaneous baroreflex functioning in adult borderline hypertensive rats and normotensive control animals kept on normal-salt diet. Arterial pulse pressure was recorded by radio telemetry. Systolic BP, diastolic BP and HR variabilities and baroreflex were assessed by spectral analysis and the sequence method, respectively. In all experimental conditions (baseline and stress), borderline hypertensive rats exhibited higher BP, increased baroreflex sensitivity and resetting, relative to control animals. Acute shaker stress (single exposure to 200 cycles min-1 shaking platform) increased BP in both strains, while chronic shaker stress (3-day exposure to shaking platform) increased systolic BP in borderline hypertensive rats alone. Low- and high-frequency HR variability increased only in control animals in response to acute and chronic shaker (single exposure to restrainer) stress. Acute restraint stress increased BP, HR, low- and high-frequency variability of BP and HR in both strains to a greater extent than acute shaker stress. Only normotensive rats exhibited a reduced ratio of low- to high-frequency HR variability, pointing to domination of vagal cardiac control. In borderline hypertensive rats, but not in control animals, chronic restraint stress (9-day exposure to restrainer) increased low- and high-frequency BP and HR variability and their ratio, indicating a shift towards sympathetic cardiovascular control. It is concluded that maintenance of BP in borderline hypertensive rats in basal conditions and during stress is associated with enhanced baroreflex sensitivity and resetting. Imbalance in sympathovagal control was evident only during exposure of borderline hypertensive rats to stressors. PMID:21421701

  15. Autonomic mechanisms underpinning the stress response in borderline hypertensive rats.

    PubMed

    Šarenac, Olivera; Lozić, Maja; Drakulić, Srdja; Bajić, Dragana; Paton, Julian F; Murphy, David; Japundžić-Žigon, Nina

    2011-06-01

    This study investigates blood pressure (BP) and heart rate (HR) short-term variability and spontaneous baroreflex functioning in adult borderline hypertensive rats and normotensive control animals kept on normal-salt diet. Arterial pulse pressure was recorded by radio telemetry. Systolic BP, diastolic BP and HR variabilities and baroreflex were assessed by spectral analysis and the sequence method, respectively. In all experimental conditions (baseline and stress), borderline hypertensive rats exhibited higher BP, increased baroreflex sensitivity and resetting, relative to control animals. Acute shaker stress (single exposure to 200 cycles min-1 shaking platform) increased BP in both strains, while chronic shaker stress (3-day exposure to shaking platform) increased systolic BP in borderline hypertensive rats alone. Low- and high-frequency HR variability increased only in control animals in response to acute and chronic shaker (single exposure to restrainer) stress. Acute restraint stress increased BP, HR, low- and high-frequency variability of BP and HR in both strains to a greater extent than acute shaker stress. Only normotensive rats exhibited a reduced ratio of low- to high-frequency HR variability, pointing to domination of vagal cardiac control. In borderline hypertensive rats, but not in control animals, chronic restraint stress (9-day exposure to restrainer) increased low- and high-frequency BP and HR variability and their ratio, indicating a shift towards sympathetic cardiovascular control. It is concluded that maintenance of BP in borderline hypertensive rats in basal conditions and during stress is associated with enhanced baroreflex sensitivity and resetting. Imbalance in sympathovagal control was evident only during exposure of borderline hypertensive rats to stressors.

  16. 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

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

    PubMed

    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.

  18. Oxidative and nitrosative stress in trichloroethene-mediated autoimmune response.

    PubMed

    Wang, Gangduo; Cai, Ping; Ansari, G A S; Khan, M Firoze

    2007-01-18

    Reactive oxygen and nitrogen species (RONS) are implicated in the pathogenesis of several autoimmune diseases. Also, increased lipid peroxidation and protein nitration are reported in systemic autoimmune diseases. Lipid peroxidation-derived aldehydes (LPDAs) such as malondialdehyde (MDA) and 4-hydroxynonenal (HNE) are highly reactive and bind proteins covalently, but their potential to elicit an autoimmune response and contribution to disease pathogenesis remain unclear. Similarly, nitration of protein could also contribute to disease pathogenesis. To assess the status of lipid peroxidation and/or RONS, autoimmune-prone female MRL+/+ mice (5-week old) were treated with trichloroethene (TCE), an environmental contaminant known to induce autoimmune response, for 48 weeks (0.5mg/ml via drinking water), and formation of antibodies to LPDA-protein adducts was followed in the sera of control and TCE-treated mice. TCE treatment led to greater formation of both anti-MDA- and -HNE-protein adduct antibodies and higher serum iNOS and nitrotyrosine levels. The increase in TCE-induced oxidative stress was associated with increases in anti-nuclear-, anti-ssDNA- and anti-dsDNA-antibodies. These findings suggest that TCE exposure not only leads to oxidative/nitrosative stress, but is also associated with induction/exacerbation of autoimmune response in MRL+/+ mice. Further interventional studies are needed to establish a causal role of RONS in TCE-mediated autoimmunity.

  19. Response of Saccharomyces cerevisiae to stress-free acidification.

    PubMed

    Chen, Allen Kuan-Liang; Gelling, Cristy; Rogers, Peter L; Dawes, Ian W; Rosche, Bettina

    2009-02-01

    Genome-wide transcriptional analysis of a Saccharomyces cerevisiae batch culture revealed that more than 829 genes were regulated in response to an environmental shift from pH 6 to pH 3 by added sulfuric acid. This shift in pH was not detrimental to the rate of growth compared to a control culture that was maintained at pH 6 and the transcriptional changes most strikingly implicated not up- but down-regulation of stress responses. In addition, the transcriptional changes upon acid addition indicated remodeling of the cell wall and central carbon metabolism. The overall trend of changes was similar for the pH-shift experiment and the pH 6 control. However, the changes in the pH 6 control were much weaker and occurred 2.5 h later than in the pH-shift experiment. Thus, the reaction to the steep pH decrease was an immediate response within the normal repertoire of adaptation shown in later stages of fermentation at pH 6. Artificially preventing the yeast from acidifying the medium may be considered physiologically stressful under the tested conditions.

  20. Human endothelial cell responses to cardiovascular inspired pulsatile shear stress

    NASA Astrophysics Data System (ADS)

    Watson, Matthew; Baugh, Lauren; Black, Lauren, III; Kemmerling, Erica

    2016-11-01

    It is well established that hemodynamic shear stress regulates blood vessel structure and the development of vascular pathology. This process can be studied via in vitro models of endothelial cell responses to pulsatile shear stress. In this study, a macro-scale cone and plate viscometer was designed to mimic various shear stress waveforms found in the body and apply these stresses to human endothelial cells. The device was actuated by a PID-controlled DC gear-motor. Cells were exposed to 24 hours of pulsatile shear and then imaged and stained to track their morphology and secretions. These measurements were compared with control groups of cells exposed to constant shear and no shear. The results showed that flow pulsatility influenced levels of secreted proteins such as VE-cadherin and neuroregulin IHC. Cell morphology was also influenced by flow pulsatility; in general cells exposed to pulsatile shear stress developed a higher aspect ratio than cells exposed to no flow but a lower aspect ratio than cells exposed to steady flow.

  1. Magnitude-dependent response of osteoblasts regulated by compressive stress

    PubMed Central

    Shen, Xiao-qing; Geng, Yuan-ming; Liu, Ping; Huang, Xiang-yu; Li, Shu-yi; Liu, Chun-dong; Zhou, Zheng; Xu, Ping-ping

    2017-01-01

    The present study aimed to investigate the role of magnitude in adaptive response of osteoblasts exposed to compressive stress. Murine primary osteoblasts and MC3T3-E1 cells were exposed to compressive stress (0, 1, 2, 3, 4, and 5 g/cm2) in 3D culture. Cell viability was evaluated, and expression levels of Runx2, Alp, Ocn, Rankl, and Opg were examined. ALP activity in osteoblasts and TRAP activity in RAW264.7 cells co-cultured with MC3T3-E1 cells were assayed. Results showed that compressive stress within 5.0 g/cm2 did not influence cell viability. Both osteoblastic and osteoblast-regulated osteoclastic differentiation were enhanced at 2 g/cm2. An increase in stress above 2 g/cm2 did not enhance osteoblastic differentiation further but significantly inhibited osteoblast-regualted osteoclastic differentiation. This study suggested that compressive stress regulates osteoblastic and osteoclastic differentiation through osteoblasts in a magnitude-dependent manner. PMID:28317941

  2. Pairing of heterochromatin in response to cellular stress

    SciTech Connect

    Abdel-Halim, H.I.; Mullenders, L.H.F. . E-mail: L.Mullenders@lumc.nl; Boei, J.J.W.A.

    2006-07-01

    We previously reported that exposure of human cells to DNA-damaging agents (X-rays and mitomycin C (MMC)) induces pairing of the homologous paracentromeric heterochromatin of chromosome 9 (9q12-13). Here, we show that UV irradiation and also heat shock treatment of human cells lead to similar effects. Since the various agents induce very different types and frequencies of damage to cellular constituents, the data suggest a general stress response as the underlying mechanism. Moreover, local UV irradiation experiments revealed that pairing of heterochromatin is an event that can be triggered without induction of DNA damage in the heterochromatic sequences. The repair deficient xeroderma pigmentosum cells (group F) previously shown to fail pairing after MMC displayed elevated pairing after heat shock treatment but not after UV exposure. Taken together, the present results indicate that pairing of heterochromatin following exposure to DNA-damaging agents is initiated by a general stress response and that the sensing of stress or the maintenance of the paired status of the heterochromatin might be dependent on DNA repair.

  3. 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.

  4. Time kinetics of the endocrine response to acute psychological stress.

    PubMed

    Richter, S D; Schürmeyer, T H; Schedlowski, M; Hädicke, A; Tewes, U; Schmidt, R E; Wagner, T O

    1996-05-01

    A first-time parachute jump was chosen as a model to evaluate the endocrine response to acute psychological stress. In 43 inexperienced tandem parachutists, blood was drawn continuously from 2 h before to 1 h after the jump and analyzed at 10-min intervals for plasma concentrations of epinephrine (E), norepinephrine (NE), cortisol, GH, PRL, and TSH. In addition, heart rate was recorded throughout the experiment. There was a significant increase in heart rate and E concentrations during the jump itself. NE, cortisol, GH, PRL, and TSH peaked with a latency of 10-20 min. Apart from cortisol and TSH concentrations, which were still elevated 1 h after the stress event, plasma levels of the other endocrine variables normalized within 1 h following the jump. Statistically significant cross-correlations could be observed between E and NE (r = 0.60, no time lag) and between E and PRL (r = 0.58, 10-min time lag) only. Even in a very homogenous group of subjects and under well-controlled conditions, endocrine responses to acute psychological stress show considerable variations.

  5. Yeast responses to stresses associated with industrial brewery handling.

    PubMed

    Gibson, Brian R; Lawrence, Stephen J; Leclaire, Jessica P R; Powell, Chris D; Smart, Katherine A

    2007-09-01

    During brewery handling, production strains of yeast must respond to fluctuations in dissolved oxygen concentration, pH, osmolarity, ethanol concentration, nutrient supply and temperature. Fermentation performance of brewing yeast strains is dependent on their ability to adapt to these changes, particularly during batch brewery fermentation which involves the recycling (repitching) of a single yeast culture (slurry) over a number of fermentations (generations). Modern practices, such as the use of high-gravity worts and preparation of dried yeast for use as an inoculum, have increased the magnitude of the stresses to which the cell is subjected. The ability of yeast to respond effectively to these conditions is essential not only for beer production but also for maintaining the fermentation fitness of yeast for use in subsequent fermentations. During brewery handling, cells inhabit a complex environment and our understanding of stress responses under such conditions is limited. The advent of techniques capable of determining genomic and proteomic changes within the cell is likely vastly to improve our knowledge of yeast stress responses during industrial brewery handling.

  6. Ancestry trumps experience: Transgenerational but not early life stress affects the adult physiological stress response.

    PubMed

    McCormick, Gail L; Robbins, Travis R; Cavigelli, Sonia A; Langkilde, Tracy

    2017-01-01

    Exposure to stressors can affect an organism's physiology and behavior as well as that of its descendants (e.g. through maternal effects, epigenetics, and/or selection). We examined the relative influence of early life vs. transgenerational stress exposure on adult stress physiology in a species that has populations with and without ancestral exposure to an invasive predator. We raised offspring of eastern fence lizards (Sceloporus undulatus) from sites historically invaded (high stress) or uninvaded (low stress) by predatory fire ants (Solenopsis invicta) and determined how this different transgenerational exposure to stress interacted with the effects of early life stress exposure to influence the physiological stress response in adulthood. Offspring from these high- and low-stress populations were exposed weekly to either sub-lethal attack by fire ants (an ecologically relevant stressor), topical treatment with a physiologically-appropriate dose of the stress-relevant hormone, corticosterone (CORT), or a control treatment from 2 to 43weeks of age. Several months after treatments ended, we quantified plasma CORT concentrations at baseline and following restraint, exposure to fire ants, and adrenocorticotropic hormone (ACTH) injection. Exposure to fire ants or CORT during early life did not affect lizard stress physiology in adulthood. However, offspring of lizards from populations that had experienced multiple generations of fire ant-invasion exhibited more robust adult CORT responses to restraint and ACTH-injection compared to offspring from uninvaded populations. Together, these results indicate that transgenerational stress history may be at least as important, if not more important, than early life stress in affecting adult physiological stress responses.

  7. Antioxidant responses and cellular adjustments to oxidative stress.

    PubMed

    Espinosa-Diez, Cristina; Miguel, Verónica; Mennerich, Daniela; Kietzmann, Thomas; Sánchez-Pérez, Patricia; Cadenas, Susana; Lamas, Santiago

    2015-12-01

    Redox biological reactions are now accepted to bear the Janus faceted feature of promoting both physiological signaling responses and pathophysiological cues. Endogenous antioxidant molecules participate in both scenarios. This review focuses on the role of crucial cellular nucleophiles, such as glutathione, and their capacity to interact with oxidants and to establish networks with other critical enzymes such as peroxiredoxins. We discuss the importance of the Nrf2-Keap1 pathway as an example of a transcriptional antioxidant response and we summarize transcriptional routes related to redox activation. As examples of pathophysiological cellular and tissular settings where antioxidant responses are major players we highlight endoplasmic reticulum stress and ischemia reperfusion. Topologically confined redox-mediated post-translational modifications of thiols are considered important molecular mechanisms mediating many antioxidant responses, whereas redox-sensitive microRNAs have emerged as key players in the posttranscriptional regulation of redox-mediated gene expression. Understanding such mechanisms may provide the basis for antioxidant-based therapeutic interventions in redox-related diseases.

  8. Antioxidant responses and cellular adjustments to oxidative stress

    PubMed Central

    Espinosa-Diez, Cristina; Miguel, Verónica; Mennerich, Daniela; Kietzmann, Thomas; Sánchez-Pérez, Patricia; Cadenas, Susana; Lamas, Santiago

    2015-01-01

    Redox biological reactions are now accepted to bear the Janus faceted feature of promoting both physiological signaling responses and pathophysiological cues. Endogenous antioxidant molecules participate in both scenarios. This review focuses on the role of crucial cellular nucleophiles, such as glutathione, and their capacity to interact with oxidants and to establish networks with other critical enzymes such as peroxiredoxins. We discuss the importance of the Nrf2-Keap1 pathway as an example of a transcriptional antioxidant response and we summarize transcriptional routes related to redox activation. As examples of pathophysiological cellular and tissular settings where antioxidant responses are major players we highlight endoplasmic reticulum stress and ischemia reperfusion. Topologically confined redox-mediated post-translational modifications of thiols are considered important molecular mechanisms mediating many antioxidant responses, whereas redox-sensitive microRNAs have emerged as key players in the posttranscriptional regulation of redox-mediated gene expression. Understanding such mechanisms may provide the basis for antioxidant-based therapeutic interventions in redox-related diseases. PMID:26233704

  9. Stress responses in the opportunistic pathogen Acinetobacter baumannii

    PubMed Central

    Fiester, Steven E; Actis, Luis A

    2013-01-01

    Acinetobacter baumannii causes a wide range of severe infections among compromised and injured patients worldwide. The relevance of these infections are, in part, due to the ability of this pathogen to sense and react to environmental and host stress signals, allowing it to persist and disseminate in medical settings and the human host. This review summarizes current knowledge on the roles that environmental and cellular stressors play in the ability of A. baumannii to resist nutrient deprivation, oxidative and nitrosative injury, and even the presence of the commonly used antiseptic ethanol, which could serve as a nutrient- and virulence-enhancing signal rather than just being a convenient disinfectant. Emerging experimental evidence supports the role of some of these responses in the pathogenesis of the infections A. baumannii causes in humans and its capacity to resist antibiotics and host response effectors. PMID:23464372

  10. Aneuploidy triggers a TFEB-mediated lysosomal stress response

    PubMed Central

    Santaguida, Stefano; Amon, Angelika

    2015-01-01

    Aneuploidy, defined as an alteration in chromosome number that is not a multiple of the haploid complement, severely affects cellular physiology. Changes in chromosome number lead to imbalances in cellular protein composition, thus disrupting cellular processes and causing proteins to misfold and aggregate. We recently reported that in mammalian cells protein aggregates are readily encapsulated within autophagosomes but are not degraded by lysosomes. This leads to a lysosomal stress response in which the transcription factor TFEB induces expression of factors needed for macroautophagy-mediated protein degradation. Our studies uncover lysosomal degradation defects as a feature of the aneuploid state, and a role for the transcription factor TFEB in the response thereto. PMID:26571033

  11. 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.

  12. Response to stress in Drosophila is mediated by gender, age and stress paradigm

    PubMed Central

    Neckameyer, Wendi S.; Nieto, Andres

    2016-01-01

    All living organisms must maintain equilibrium in response to internal and external challenges within their environment. Changes in neural plasticity (alterations in neuronal populations, dendritic remodeling, and synaptic turnover) are critical components of the homeostatic response to stress, which has been strongly implicated in the onset of affective disorders. However, stress is differentially perceived depending on the type of stress and its context, as well as genetic background, age and sex; therefore, an individual’s maintenance of neuronal homeostasis must differ depending upon these variables. We established Drosophila as a model to analyze homeostatic responses to stress. Sexually immature and mature females and males from an isogenic wild-type strain raised under controlled environmental conditions were exposed to four reproducible and high-throughput translatable stressors to facilitate the analysis of a large number of animals for direct comparisons. These animals were assessed in an open-field arena, in a Light-Dark Box, and in a Forced Swim Test, as well as for sensitivity to the sedative effects of ethanol. These studies establish that immature and mature females and males represent behaviorally distinct populations under control conditions as well as after exposure to different stressors. Therefore, the neural substrates mediating the stress response must be differentially expressed depending upon the hormonal status of the brain. In addition, an adaptive response to a given stressor in one paradigm was not predictive for outcomes in other paradigms. PMID:25783197

  13. Response to stress in Drosophila is mediated by gender, age and stress paradigm.

    PubMed

    Neckameyer, Wendi S; Nieto-Romero, Andres R

    2015-01-01

    All living organisms must maintain equilibrium in response to internal and external challenges within their environment. Changes in neural plasticity (alterations in neuronal populations, dendritic remodeling, and synaptic turnover) are critical components of the homeostatic response to stress, which has been strongly implicated in the onset of affective disorders. However, stress is differentially perceived depending on the type of stress and its context, as well as genetic background, age and sex; therefore, an individual's maintenance of neuronal homeostasis must differ depending upon these variables. We established Drosophila as a model to analyze homeostatic responses to stress. Sexually immature and mature females and males from an isogenic wild-type strain raised under controlled environmental conditions were exposed to four reproducible and high-throughput translatable stressors to facilitate the analysis of a large number of animals for direct comparisons. These animals were assessed in an open-field arena, in a light-dark box, and in a forced swim test, as well as for sensitivity to the sedative effects of ethanol. These studies establish that immature and mature females and males represent behaviorally distinct populations under control conditions as well as after exposure to different stressors. Therefore, the neural substrates mediating the stress response must be differentially expressed depending upon the hormonal status of the brain. In addition, an adaptive response to a given stressor in one paradigm was not predictive for outcomes in other paradigms.

  14. Stretching the stress boundary: Linking air pollution health effects to a neurohormonal stress response.

    PubMed

    Kodavanti, Urmila P

    2016-12-01

    Inhaled pollutants produce effects in virtually all organ systems in our body and have been linked to chronic diseases including hypertension, atherosclerosis, Alzheimer's and diabetes. A neurohormonal stress response (referred to here as a systemic response produced by activation of the sympathetic nervous system and hypothalamus-pituitary-adrenal (HPA)-axis) has been implicated in a variety of psychological and physical stresses, which involves immune and metabolic homeostatic mechanisms affecting all organs in the body. In this review, we provide new evidence for the involvement of this well-characterized neurohormonal stress response in mediating systemic and pulmonary effects of a prototypic air pollutant - ozone. A plethora of systemic metabolic and immune effects are induced in animals exposed to inhaled pollutants, which could result from increased circulating stress hormones. The release of adrenal-derived stress hormones in response to ozone exposure not only mediates systemic immune and metabolic responses, but by doing so, also modulates pulmonary injury and inflammation. With recurring pollutant exposures, these effects can contribute to multi-organ chronic conditions associated with air pollution. This review will cover, 1) the potential mechanisms by which air pollutants can initiate the relay of signals from respiratory tract to brain through trigeminal and vagus nerves, and activate stress responsive regions including hypothalamus; and 2) the contribution of sympathetic and HPA-axis activation in mediating systemic homeostatic metabolic and immune effects of ozone in various organs. The potential contribution of chronic environmental stress in cardiovascular, neurological, reproductive and metabolic diseases, and the knowledge gaps are also discussed. This article is part of a Special Issue entitled Air Pollution, edited by Wenjun Ding, Andrew J. Ghio and Weidong Wu.

  15. Stress response induced by carbon nanoparticles in Paracentrotus lividus

    PubMed Central

    Carata, Elisabetta; Anna Tenuzzo, Bernardetta; Arnò, Federica; Buccolieri, Alessandro; Serra, Antonio; Manno, Daniela; Dini, Luciana

    2012-01-01

    Members of the 14-3-3 protein family are involved in many important cellular events, including stress response, survival and apoptosis. Genes of the 14-3-3 family are conserved from plants to humans, and some members are responsive to UV radiation. Despite the high rate of pollution generated by nano-pollutants, up to now their toxic effect on development is totally obscure. Embryos treated with carbon nanoparticles, RNA preparation, retro-transcription and quantitative real-time PCR. In response to carbon nano-particles exposure, the embryos collected 24 h later showed a 3,07-fold at 5x1012 p and a 1,58-fold at 2.5x1013 p and a 1,92-fold at 2.5x1014 p increase in Pl14-3-3ε transcript levels compared with controls. The Pl14-3-3ε mRNA delocalization parallels the failure in archenteron elongation observed morphologically, as well as the lack of specific endoderm markers. Here, we report the isolation of the complete cDNA encoding the 14-3-3 epsilon isoform from Paracentrotus lividus sea urchin embryos, referred to as Pl14-3-3ε. Pl14-3-3ε mRNA levels were measured by RT-PCR during development and found to increase from the mesenchyme blastula to the prism stage. Our results confirm the involvement of 14-3-3ε in the stress response elicited by carbon nano-particles. PMID:24551756

  16. Stress response induced by carbon nanoparticles in Paracentrotus lividus.

    PubMed

    Carata, Elisabetta; Anna Tenuzzo, Bernardetta; Arnò, Federica; Buccolieri, Alessandro; Serra, Antonio; Manno, Daniela; Dini, Luciana

    2012-01-01

    Members of the 14-3-3 protein family are involved in many important cellular events, including stress response, survival and apoptosis. Genes of the 14-3-3 family are conserved from plants to humans, and some members are responsive to UV radiation. Despite the high rate of pollution generated by nano-pollutants, up to now their toxic effect on development is totally obscure. Embryos treated with carbon nanoparticles, RNA preparation, retro-transcription and quantitative real-time PCR. In response to carbon nano-particles exposure, the embryos collected 24 h later showed a 3,07-fold at 5x10(12) p and a 1,58-fold at 2.5x10(13) p and a 1,92-fold at 2.5x10(14) p increase in Pl14-3-3ε transcript levels compared with controls. The Pl14-3-3ε mRNA delocalization parallels the failure in archenteron elongation observed morphologically, as well as the lack of specific endoderm markers. Here, we report the isolation of the complete cDNA encoding the 14-3-3 epsilon isoform from Paracentrotus lividus sea urchin embryos, referred to as Pl14-3-3ε. Pl14-3-3ε mRNA levels were measured by RT-PCR during development and found to increase from the mesenchyme blastula to the prism stage. Our results confirm the involvement of 14-3-3ε in the stress response elicited by carbon nano-particles.

  17. Transcriptional profiling of Giardia intestinalis in response to oxidative stress.

    PubMed

    Ma'ayeh, Showgy Y; Knörr, Livia; Svärd, Staffan G

    2015-12-01

    Giardia intestinalis is a microaerophilic parasite that infects the human upper small intestine, an environment that is fairly aerobic with reactive oxygen species being produced to fight off the parasite. It is quite perplexing how Giardia, lacking conventional eukaryotic antioxidant machinery (e.g. catalase, superoxide dismutase and glutathione peroxidase), can cope with the oxidative stress in this environment. We used transcriptomics (RNA sequencing and quantitative PCR) to study giardial gene expression changes in response to oxygen (O2; 1h) and hydrogen peroxide (H2O2; 150 μM, 500 μM and 1mM for 1h). The results showed phenotypic and transcriptional differences between Giardia isolates of different genotypes (WB, assemblage A and GS, assemblage B), with GS being more tolerant to H2O2 and exhibiting higher basic transcript levels of antioxidant genes (e.g. NADH oxidase lateral transfer candidate, peroxiredoxin 1 (Prx1) and thioredoxin (Trx)-like proteins). Cysteine is a major antioxidant in Giardia and its role in oxidative defense could be highlighted here by the up-regulation of gene transcripts encoding the cysteine-rich variable surface proteins (VSPs) and high cysteine membrane proteins (HCMPs). Genes in the thioredoxin system (Prx1, Trx and Trx reductase) occupied a central role in the gene expression response to oxidative stress, together with genes encoding metabolic (NADPH-producing enzymes, glutathione and glycerol biosynthetic enzymes) and O2-consuming nitric oxide detoxification enzymes (e.g. nitroreductase, flavohemoprotein and a flavodiiron protein). This study reveals the intricate network of genes associated with the oxidative stress response in Giardia, and provides a stepping-stone towards future studies at the protein level.

  18. Differential stress response mechanisms in right and left ventricles.

    PubMed

    Zungu-Edmondson, Makhosazane; Suzuki, Yuichiro J

    2016-01-01

    Right ventricular (RV) failure is the major cause of death among patients with pulmonary hypertension. However, differences between the RV and left ventricle (LV) of the adult heart have not been defined, despite myocytes from these two ventricles originate from different progenitor cells. The lack of such knowledge interferes with developing therapeutic strategies to protect the RV. The goal of this study was to identify possible differences between stress responses in the RV and LV free walls of adult rats. We found that levels of angiogenesis and autophagy/mitophagy proteins are higher in the LV than in the RV. Thus, the LV may be more resistant to stress-induced damage. To test this, isolated rat hearts were subjected to biventricular working heart perfusion and ischemia/reperfusion (I/R) injury. However, I/R was found to cause apoptosis in both LV and RV to a similar extent. One mechanism of cardiac apoptosis involves downregulation of GATA4 transcription factor that controls gene transcription of anti-apoptotic Bcl-xL. Interestingly, only in the RV, I/R caused downregulation of GATA4 and Bcl-xL, suggesting that mechanisms of apoptosis may be different between the two ventricles. Levels of tropomyosin and troponin T were also found to be decreased in response to I/R only in the RV, but not in the LV. Downregulation of the GATA4/Bcl-xL axis and the reduction of tropomyosin and troponin T are RV-specific events that occur in response to stress. This information may be useful for designing RV-specific therapeutic strategies to treat RV failure in pulmonary hypertension patients.

  19. Cell identity regulators link development and stress responses in the Arabidopsis root.

    PubMed

    Iyer-Pascuzzi, Anjali S; Jackson, Terry; Cui, Hongchang; Petricka, Jalean J; Busch, Wolfgang; Tsukagoshi, Hironaka; Benfey, Philip N

    2011-10-18

    Stress responses in plants are tightly coordinated with developmental processes, but interaction of these pathways is poorly understood. We used genome-wide assays at high spatiotemporal resolution to understand the processes that link development and stress in the Arabidopsis root. Our meta-analysis finds little evidence for a universal stress response. However, common stress responses appear to exist with many showing cell type specificity. Common stress responses may be mediated by cell identity regulators because mutations in these genes resulted in altered responses to stress. Evidence for a direct role for cell identity regulators came from genome-wide binding profiling of the key regulator SCARECROW, which showed binding to regulatory regions of stress-responsive genes. Coexpression in response to stress was used to identify genes involved in specific developmental processes. These results reveal surprising linkages between stress and development at cellular resolution, and show the power of multiple genome-wide data sets to elucidate biological processes.

  20. Stress, and pathogen response gene expression in modeled microgravity

    NASA Technical Reports Server (NTRS)

    Sundaresan, Alamelu; Pellis, Neal R.

    2006-01-01

    Purpose: Immune suppression in microgravity has been well documented. With the advent of human exploration and long-term space travel, the immune system of the astronaut must be optimally maintained. It is important to investigate the expression patterns of cytokine genes, because they are directly related to immune response. Heat shock proteins (HSPs), also called stress proteins, are a group of proteins that are present in the cells of every life form. These proteins are induced when a cell responds to stressors such as heat, cold and oxygen deprivation. Microgravity is another stressor that may regulate HSPs. Heat shock proteins trigger immune response through activities that occur both inside the cell (intracellular) and outside the cell (extracellular). Knowledge about these two gene groups could lead to establishment of a blueprint of the immune response and adaptation-related genes in the microgravity environment. Methods: Human peripheral blood cells were cultured in 1g (T flask) and modeled microgravity (MMG, rotating-wall vessel) for 24 and 72 hours. Cell samples were collected and subjected to gene array analysis using the Affymetrix HG_U95 array. Data was collected and subjected to a two-way analysis of variance. The genes related to immune and stress responses were analyzed. Results and Conclusions: HSP70 was up-regulated by more than two fold in microgravity culture, while HSP90 was significantly down-regulated. HSP70 is not typically expressed in all kinds of cells, but it is expressed at high levels in stress conditions. HSP70 participates in translation, protein translocation, proteolysis and protein folding, suppressing aggregation and reactivating denatured proteins. Increased serum HSP70 levels correlate with a better outcome for heat-stroke or severe trauma patients. At the same time, elevated serum levels of HSP70 have been detected in patients with peripheral or renal vascular disease. HSP90 has been identified in the cytosol, nucleus and

  1. Transcriptional regulatory networks in cellular responses and tolerance to dehydration and cold stresses.

    PubMed

    Yamaguchi-Shinozaki, Kazuko; Shinozaki, Kazuo

    2006-01-01

    Plant growth and productivity are greatly affected by environmental stresses such as drought, high salinity, and low temperature. Expression of a variety of genes is induced by these stresses in various plants. The products of these genes function not only in stress tolerance but also in stress response. In the signal transduction network from perception of stress signals to stress-responsive gene expression, various transcription factors and cis-acting elements in the stress-responsive promoters function for plant adaptation to environmental stresses. Recent progress has been made in analyzing the complex cascades of gene expression in drought and cold stress responses, especially in identifying specificity and cross talk in stress signaling. In this review article, we highlight transcriptional regulation of gene expression in response to drought and cold stresses, with particular emphasis on the role of transcription factors and cis-acting elements in stress-inducible promoters.

  2. Modulating the pituitary-adrenal response to stress

    NASA Technical Reports Server (NTRS)

    Vernikos-Danellis, J.

    1975-01-01

    Serotonin is believed to be a transmitter or regulator of neuronal function. A possible relationship between the pituitary-adrenal secretion of steroids and brain serotonin in the rat was investigated by evaluating the effects of altering brain 5-hydroxy tryptamine (HT) levels on the daily fluctuation of plasma corticosterone and on the response of the pituitary-adrenal system to a stressful or noxious stimulus in the rat. The approach was either to inhibit brain 5-HT synthesis with para-chlorophenyl alanine or to raise its level with precursors such as tryptophan or 5-hydroxy tryptophan.

  3. Cardiovascular responses to heat stress in chronic heart failure

    PubMed Central

    Cui, Jian; Sinoway, Lawrence I.

    2014-01-01

    Clinical reports have suggested that patients with heart diseases may be particularly vulnerable to heat injury. This review examines the effects of heat stress on cardiovascular and autonomic functions in patients with chronic heart failure (CHF). Laboratory investigations have shown that cutaneous vasodilator responses to heating are impaired in patients, whereas activation of skin sympathetic nerve activation is not attenuated in CHF as compared to controls. Attenuated cutaneous vasodilation may increase the risk of a heat related illness when CHF subjects are exposed to hyperthermic conditions. PMID:24599558

  4. Oxidative stress, unfolded protein response, and apoptosis in developmental toxicity.

    PubMed

    Kupsco, Allison; Schlenk, Daniel

    2015-01-01

    Physiological development requires precise spatiotemporal regulation of cellular and molecular processes. Disruption of these key events can generate developmental toxicity in the form of teratogenesis or mortality. The mechanism behind many developmental toxicants remains unknown. While recent work has focused on the unfolded protein response (UPR), oxidative stress, and apoptosis in the pathogenesis of disease, few studies have addressed their relationship in developmental toxicity. Redox regulation, UPR, and apoptosis are essential for physiological development and can be disturbed by a variety of endogenous and exogenous toxicants to generate lethality and diverse malformations. This review examines the current knowledge of the role of oxidative stress, UPR, and apoptosis in physiological development as well as in developmental toxicity, focusing on studies and advances in vertebrates model systems.

  5. Adrenal cortical response to stress at Three Mile Island.

    PubMed

    Schaeffer, M A; Baum, A

    1984-01-01

    The present study examined the relationship between biochemical, psychologic, and behavioral components of chronic stress associated with living near the damaged nuclear power plant at Three Mile Island (TMI). Relative to control subjects, TMI subjects had higher levels of urinary cortisol, which correlated significantly with urinary catecholamines, self-report of physical and mental symptoms, and decrements in task performance. Further, it was found that males had higher urinary cortisol levels than females at TMI, while at the control sites, levels of cortisol were comparable between males and females. Finally, no significant relationship between coping style and urinary cortisol was detected. Levels of stress response among TMI are residents, though significantly greater than control subjects, were within normal ranges and thus should be considered subclinical in intensity. Their persistence over 17 months, however, suggests some cause for concern.

  6. The cortisol response to social stress in social anxiety disorder.

    PubMed

    Vaccarino, Oriana; Levitan, Robert; Ravindran, Arun

    2015-04-01

    This study evaluated the cortisol stress response (CSR) following the Trier Social Stress Test in Social Anxiety Disorder (SAD) and control participants, to determine whether individual differences in CSR associate more with SAD diagnosis or dimensional characteristics [i.e. childhood trauma (CT)]. Twenty-one participants (11 with SAD) had full data available for both CT-scores and cortisol area-under-the-curve (AUC). Linear regression produced significant results: predicting AUCG with study group, emotional abuse (EA) scores and their interaction (F=3.14, df=5,15; p=.039); of note, the study group by EA interaction was significant at p=.015, driven by a strong positive association between EA and cortisol AUCG in the control group, and a negative association between these variables in the SAD group (standardized-beta=1.56, t=2.75, p=.015). This suggests that EA in SAD patients is associated with altered CSR, highlighting need to measure dimensional characteristics.

  7. Histone variants and chromatin assembly in plant abiotic stress responses.

    PubMed

    Zhu, Yan; Dong, Aiwu; Shen, Wen-Hui

    2013-01-01

    Genome organization into nucleosomes and higher-order chromatin structures has profound implications for the regulation of gene expression, DNA replication and repair. The structure of chromatin can be remodeled by several mechanisms; among others, nucleosome assembly/disassembly and replacement of canonical histones with histone variants constitute important ones. In this review, we provide a brief description on the current knowledge about histone chaperones involved in nucleosome assembly/disassembly and histone variants in Arabidopsis thaliana. We discuss recent advances in revealing crucial functions of histone chaperones, nucleosome assembly/disassembly and histone variants in plant response to abiotic stresses. It appears that chromatin structure remodeling may provide a flexible, global and stable means for the regulation of gene transcription to help plants more effectively cope with environmental stresses. This article is part of a Special Issue entitled: Histone chaperones and chromatin assembly.

  8. Microtubules self-repair in response to mechanical stress

    NASA Astrophysics Data System (ADS)

    Schaedel, Laura; John, Karin; Gaillard, Jérémie; Nachury, Maxence V.; Blanchoin, Laurent; Théry, Manuel

    2015-11-01

    Microtubules--which define the shape of axons, cilia and flagella, and provide tracks for intracellular transport--can be highly bent by intracellular forces, and microtubule structure and stiffness are thought to be affected by physical constraints. Yet how microtubules tolerate the vast forces exerted on them remains unknown. Here, by using a microfluidic device, we show that microtubule stiffness decreases incrementally with each cycle of bending and release. Similar to other cases of material fatigue, the concentration of mechanical stresses on pre-existing defects in the microtubule lattice is responsible for the generation of more extensive damage, which further decreases microtubule stiffness. Strikingly, damaged microtubules were able to incorporate new tubulin dimers into their lattice and recover their initial stiffness. Our findings demonstrate that microtubules are ductile materials with self-healing properties, that their dynamics does not exclusively occur at their ends, and that their lattice plasticity enables the microtubules' adaptation to mechanical stresses.

  9. Oxidative stress response and Nrf2 signaling in aging

    PubMed Central

    Zhang, Hongqiao; Davies, Kelvin J. A.; Forman, Henry Jay

    2015-01-01

    Increasing oxidative stress, a major characteristic of aging, has been implicated in variety of age-related pathologies. In aging, oxidant production from several sources is increased while antioxidant enzymes, the primary lines of defense, are decreased. Repair systems, including the proteasomal degradation of damaged proteins also declines. Importantly, the adaptive response to oxidative stress declines with aging. Nrf2/EpRE signaling regulates the basal and inducible expression of many antioxidant enzymes and the proteasome. Nrf2/EpRE activity is regulated at several levels including transcription, post-translation, and interaction with other proteins. This review summarizes current studies on age-related impairment of Nrf2/EpRE function and discusses the change of Nrf2 regulatory mechanisms with aging. PMID:26066302

  10. Oxidative Stress, Unfolded Protein Response, and Apoptosis in Developmental Toxicity

    PubMed Central

    Kupsco, Allison; Schlenk, Daniel

    2016-01-01

    Physiological development requires precise spatiotemporal regulation of cellular and molecular processes. Disruption of these key events can generate developmental toxicity in the form of teratogenesis or mortality. The mechanism behind many developmental toxicants remains unknown. While recent work has focused on the unfolded protein response (UPR), oxidative stress, and apoptosis in the pathogenesis of disease, few studies have addressed their relationship in developmental toxicity. Redox regulation, UPR, and apoptosis are essential for physiological development and can be disturbed by a variety of endogenous and exogenous toxicants to generate lethality and diverse malformations. This review examines the current knowledge of the role of oxidative stress, UPR, and apoptosis in physiological development as well as in developmental toxicity, focusing on studies and advances in vertebrates model systems. PMID:26008783

  11. Stress response in Candida glabrata: pieces of a fragmented picture.

    PubMed

    Jandric, Zeljkica; Schüller, Christoph

    2011-12-01

    Candida glabrata is closely related to yeast but obviously adapted to human commensalism. Communication with the environment is important to adjust allocation of resources between protection and proliferation in order to adapt to different situations in and outside of the host. Gene transcription regulated by environmental conditions is a major response strategy of simple fungal organisms. Differences to yeast include an extended repertoire of adhesive genes, and high drug, starvation and stress resistance. These properties largely do not originate from novel virulence genes but rather from adaptations of the transcriptional wiring. C. glabrata signaling pathways providing stress protection are adopted to meet conditions possibly encountered in a host-pathogen confrontation. The view on C. glabrata is getting clearer and points to a simple strategy combining resilience and a few adaptations.

  12. Microtubules self-repair in response to mechanical stress

    PubMed Central

    Schaedel, Laura; John, Karin; Gaillard, Jérémie; Nachury, Maxence V.; Blanchoin, Laurent; Théry, Manuel

    2015-01-01

    Microtubules - which define the shape of axons, cilia and flagella, and provide tracks for intracellular transport - can be highly bent by intracellular forces, and microtubule structure and stiffness are thought to be affected by physical constraints. Yet how microtubules tolerate the vast forces exerted on them remains unknown. Here, by using a microfluidic device, we show that microtubule stiffness decreases incrementally with each cycle of bending and release. Similar to other cases of material fatigue, the concentration of mechanical stresses on pre-existing defects in the microtubule lattice is responsible for the generation of larger damages, which further decrease microtubule stiffness. Strikingly, damaged microtubules were able to incorporate new tubulin dimers into their lattice and recover their initial stiffness. Our findings demonstrate that microtubules are ductile materials with self-healing properties, that their dynamics does not exclusively occur at their ends, and that their lattice plasticity enables the microtubules' adaptation to mechanical stresses. PMID:26343914

  13. Epigenetic memory for stress response and adaptation in plants.

    PubMed

    Kinoshita, Tetsu; Seki, Motoaki

    2014-11-01

    In contrast to the majority of animal species, plants are sessile organisms and are, therefore, constantly challenged by environmental perturbations. Over the past few decades, our knowledge of how plants perceive environmental stimuli has increased considerably, e.g. the mechanisms for transducing environmental stress stimuli into cellular signaling cascades and gene transcription networks. In addition, it has recently been shown that plants can remember past environmental events and can use these memories to aid responses when these events recur. In this mini review, we focus on recent progress in determination of the epigenetic mechanisms used by plants under various environmental stresses. Epigenetic mechanisms are now known to play a vital role in the control of gene expression through small RNAs, histone modifications and DNA methylation. These are inherited through mitotic cell divisions and, in some cases, can be transmitted to the next generation. They therefore offer a possible mechanism for stress memories in plants. Recent studies have yielded evidence indicating that epigenetic mechanisms are indeed essential for stress memories and adaptation in plants.

  14. Oxidative stress responses and NRF2 in human leukaemia.

    PubMed

    Abdul-Aziz, Amina; MacEwan, David J; Bowles, Kristian M; Rushworth, Stuart A

    2015-01-01

    Oxidative stress as a result of elevated levels of reactive oxygen species (ROS) has been observed in almost all cancers, including leukaemia, where they contribute to disease development and progression. However, cancer cells also express increased levels of antioxidant proteins which detoxify ROS. This includes glutathione, the major antioxidant in human cells, which has recently been identified to have dysregulated metabolism in human leukaemia. This suggests that critical balance of intracellular ROS levels is required for cancer cell function, growth, and survival. Nuclear factor (erythroid-derived 2)-like 2 (NRF2) transcription factor plays a dual role in cancer. Primarily, NRF2 is a transcription factor functioning to protect nonmalignant cells from malignant transformation and oxidative stress through transcriptional activation of detoxifying and antioxidant enzymes. However, once malignant transformation has occurred within a cell, NRF2 functions to protect the tumour from oxidative stress and chemotherapy-induced cytotoxicity. Moreover, inhibition of the NRF2 oxidative stress pathway in leukaemia cells renders them more sensitive to cytotoxic chemotherapy. Our improved understanding of NRF2 biology in human leukaemia may permit mechanisms by which we could potentially improve future cancer therapies. This review highlights the mechanisms by which leukaemic cells exploit the NRF2/ROS response to promote their growth and survival.

  15. "Stress entropic load" as a transgenerational epigenetic response trigger.

    PubMed

    Bienertová-Vašků, Julie; Nečesánek, Ivo; Novák, Jan; Vinklárek, Jan; Zlámal, Filip

    2014-03-01

    Epigenetic changes are generally based on the switching of alternative functional or structural states and result in the adaptation of cellular expression patterns during proliferation, differentiation or plastic changes in the adult organism, whereas some epigenetic information can be passed on other generations while other is not. Hence, the principal question is: why is some information reset or resolved during the meiosis process and other is passed from one generation to another, or, in other words: what "adaptation trigger" level initiates transgenerationally transmitted epigenome change? Hereto, we propose a theory which states that stress, or, more specifically, the energy cost of an individual's adaptation to stress, represents a viable candidate for the transgenerational transmission trigger of a given acquired trait. It has been reported recently that the higher lifetime entropy generation of a unit's body mass, the higher the entropy stress level (which is a measure of energy released by a unit's organ mass) and the irreversibility within the organ, resulting in faster organ degradation and consequent health problems for the entire biological system. We therefore suggest a new term: "stress entropic load" will reflect the actual energetic cost of an individual's adaptation and may be used to estimate the probability of inducing transgenerational response once characterized or measured.

  16. Transcriptome Response Mediated by Cold Stress in Lotus japonicus

    PubMed Central

    Calzadilla, Pablo I.; Maiale, Santiago J.; Ruiz, Oscar A.; Escaray, Francisco J.

    2016-01-01

    Members of the Lotus genus are important as agricultural forage sources under marginal environmental conditions given their high nutritional value and tolerance of various abiotic stresses. However, their dry matter production is drastically reduced in cooler seasons, while their response to such conditions is not well studied. This paper analyzes cold acclimation of the genus by studying Lotus japonicus over a stress period of 24 h. High-throughput RNA sequencing was used to identify and classify 1077 differentially expressed genes, of which 713 were up-regulated and 364 were down-regulated. Up-regulated genes were principally related to lipid, cell wall, phenylpropanoid, sugar, and proline regulation, while down-regulated genes affected the photosynthetic process and chloroplast development. Together, a total of 41 cold-inducible transcription factors were identified, including members of the AP2/ERF, NAC, MYB, and WRKY families; two of them were described as putative novel transcription factors. Finally, DREB1/CBFs were described with respect to their cold stress expression profiles. This is the first transcriptome profiling of the model legume L. japonicus under cold stress. Data obtained may be useful in identifying candidate genes for breeding modified species of forage legumes that more readily acclimate to low temperatures. PMID:27066029

  17. Differential genetic interactions of yeast stress response MAPK pathways.

    PubMed

    Martin, Humberto; Shales, Michael; Fernandez-Piñar, Pablo; Wei, Ping; Molina, Maria; Fiedler, Dorothea; Shokat, Kevan M; Beltrao, Pedro; Lim, Wendell; Krogan, Nevan J

    2015-04-17

    Genetic interaction screens have been applied with great success in several organisms to study gene function and the genetic architecture of the cell. However, most studies have been performed under optimal growth conditions even though many functional interactions are known to occur under specific cellular conditions. In this study, we have performed a large-scale genetic interaction analysis in Saccharomyces cerevisiae involving approximately 49 × 1,200 double mutants in the presence of five different stress conditions, including osmotic, oxidative and cell wall-altering stresses. This resulted in the generation of a differential E-MAP (or dE-MAP) comprising over 250,000 measurements of conditional interactions. We found an extensive number of conditional genetic interactions that recapitulate known stress-specific functional associations. Furthermore, we have also uncovered previously unrecognized roles involving the phosphatase regulator Bud14, the histone methylation complex COMPASS and membrane trafficking complexes in modulating the cell wall integrity pathway. Finally, the osmotic stress differential genetic interactions showed enrichment for genes coding for proteins with conditional changes in phosphorylation but not for genes with conditional changes in gene expression. This suggests that conditional genetic interactions are a powerful tool to dissect the functional importance of the different response mechanisms of the cell.

  18. The starvation-stress response (SSR) of Salmonella.

    PubMed

    Spector, M P

    1998-01-01

    Salmonella serovars are common etiologic agents of intestinal-based disease of animals and humans. As a result of their lifestyle, salmonellae occupy and survive in a wide range of niches where they can encounter an even broader range of environmental stresses. One of the most common stresses is starvation for an essential nutrient such as a carbon/energy (C)-source. The genetic and physiologic changes that the bacterium undergoes in response to starvation-stress are referred to as the starvation-stress response or SSR. The genetic loci whose expression increases in response to the starvation-stress compose the SSR stimulon. Several loci of the SSR stimulon have been identified in Salmonella typhimurium and grouped, based on putative or known functions or products, into transport systems, C-compound catabolic enzymes, known protective enzymes, respiratory enzyme systems, regulatory proteins, virulence loci and unclassified products. The majority of loci identified are under positive control by the rpoS-encoded sigma factor, sigma S. However, a few are under (indirect) negative control by sigma S, but only during starvation-induced stationary phase. Most of the loci identified are also under either positive or negative control by the cAMP:CRP complex. For many, additional regulatory proteins (e.g. FadR, OxyR, and RelA and others) play a role in their regulation as well. Furthermore, most of the SSR loci identified are induced during other stresses or environmental conditions. For example, some are induced during P- or N-starvation, in addition to C-starvation; some are induced by extremes in pH or osmolarity; and some are induced in the intracellular environment of epithelial cells, and/or macrophages, and/or medium designed to mimic the intracellular milieu of mammalian cells (ISM). Several SSR loci are required for long-term starvation-survival (core SSR loci), e.g. narZ, dadA, stiC and rpoS. In addition, a few of the core SSR loci are also required for stress

  19. Embryonic exposure to corticosterone modifies the juvenile stress response, oxidative stress and telomere length

    PubMed Central

    Haussmann, Mark F.; Longenecker, Andrew S.; Marchetto, Nicole M.; Juliano, Steven A.; Bowden, Rachel M.

    2012-01-01

    Early embryonic exposure to maternal glucocorticoids can broadly impact physiology and behaviour across phylogenetically diverse taxa. The transfer of maternal glucocorticoids to offspring may be an inevitable cost associated with poor environmental conditions, or serve as a maternal effect that alters offspring phenotype in preparation for a stressful environment. Regardless, maternal glucocorticoids are likely to have both costs and benefits that are paid and collected over different developmental time periods. We manipulated yolk corticosterone (cort) in domestic chickens (Gallus domesticus) to examine the potential impacts of embryonic exposure to maternal stress on the juvenile stress response and cellular ageing. Here, we report that juveniles exposed to experimentally increased cort in ovo had a protracted decline in cort during the recovery phase of the stress response. All birds, regardless of treatment group, shifted to oxidative stress during an acute stress response. In addition, embryonic exposure to cort resulted in higher levels of reactive oxygen metabolites and an over-representation of short telomeres compared with the control birds. In many species, individuals with higher levels of oxidative stress and shorter telomeres have the poorest survival prospects. Given this, long-term costs of glucocorticoid-induced phenotypes may include accelerated ageing and increased mortality. PMID:22072607

  20. Individual differences in cortisol stress response predict increases in voice pitch during exam stress.

    PubMed

    Pisanski, Katarzyna; Nowak, Judyta; Sorokowski, Piotr

    2016-09-01

    Despite a long history of empirical research, the potential vocal markers of stress remain unclear. Previous studies examining speech under stress most consistently report an increase in voice pitch (the acoustic correlate of fundamental frequency, F0), however numerous studies have failed to replicate this finding. In the present study we tested the prediction that these inconsistencies are tied to variation in the severity of the stress response, wherein voice changes may be observed predominantly among individuals who show a cortisol stress response (i.e., an increase in free cortisol levels) above a critical threshold. Voice recordings and saliva samples were collected from university psychology students at baseline and again immediately prior to an oral examination. Voice recordings included both read and spontaneous speech, from which we measured mean, minimum, maximum, and the standard deviation in F0. We observed an increase in mean and minimum F0 under stress in both read and spontaneous speech, whereas maximum F0 and its standard deviation showed no systematic changes under stress. Our results confirmed that free cortisol levels increased by an average of 74% (ranging from 0 to 270%) under stress. Critically, increases in cortisol concentrations significantly predicted increases in mean F0 under stress for both speech types, but did not predict variation in F0 at baseline. On average, stress-induced increases in voice pitch occurred only when free cortisol levels more than doubled their baseline concentrations. Our results suggest that researchers examining speech under stress should control for individual differences in the magnitude of the stress response.

  1. Moving through the Stressed Genome: Emerging Regulatory Roles for Transposons in Plant Stress Response

    PubMed Central

    Negi, Pooja; Rai, Archana N.; Suprasanna, Penna

    2016-01-01

    The recognition of a positive correlation between organism genome size with its transposable element (TE) content, represents a key discovery of the field of genome biology. Considerable evidence accumulated since then suggests the involvement of TEs in genome structure, evolution and function. The global genome reorganization brought about by transposon activity might play an adaptive/regulatory role in the host response to environmental challenges, reminiscent of McClintock's original ‘Controlling Element’ hypothesis. This regulatory aspect of TEs is also garnering support in light of the recent evidences, which project TEs as “distributed genomic control modules.” According to this view, TEs are capable of actively reprogramming host genes circuits and ultimately fine-tuning the host response to specific environmental stimuli. Moreover, the stress-induced changes in epigenetic status of TE activity may allow TEs to propagate their stress responsive elements to host genes; the resulting genome fluidity can permit phenotypic plasticity and adaptation to stress. Given their predominating presence in the plant genomes, nested organization in the genic regions and potential regulatory role in stress response, TEs hold unexplored potential for crop improvement programs. This review intends to present the current information about the roles played by TEs in plant genome organization, evolution, and function and highlight the regulatory mechanisms in plant stress responses. We will also briefly discuss the connection between TE activity, host epigenetic response and phenotypic plasticity as a critical link for traversing the translational bridge from a purely basic study of TEs, to the applied field of stress adaptation and crop improvement. PMID:27777577

  2. Stress responses sculpt the insect immune system, optimizing defense in an ever-changing world.

    PubMed

    Adamo, Shelley Anne

    2017-01-01

    A whole organism, network approach can help explain the adaptive purpose of stress-induced changes in immune function. In insects, mediators of the stress response (e.g. stress hormones) divert molecular resources away from immune function and towards tissues necessary for fight-or-flight behaviours. For example, molecules such as lipid transport proteins are involved in both the stress and immune responses, leading to a reduction in disease resistance when these proteins are shifted towards being part of the stress response system. Stress responses also alter immune system strategies (i.e. reconfiguration) to compensate for resource losses that occur during fight-or flight events. In addition, stress responses optimize immune function for different physiological conditions. In insects, the stress response induces a pro-inflammatory state that probably enhances early immune responses.

  3. Assessing Cd-induced stress from plant spectral response

    NASA Astrophysics Data System (ADS)

    Kancheva, Rumiana; Georgiev, Georgi

    2014-10-01

    Remote sensing plays a significant role in local, regional and global monitoring of land covers. Ecological concerns worldwide determine the importance of remote sensing applications for the assessment of soil conditions, vegetation health and identification of stress-induced changes. The extensive industrial growth and intensive agricultural land-use arise the serious ecological problem of environmental pollution associated with the increasing anthropogenic pressure on the environment. Soil contamination is a reason for degradation processes and temporary or permanent decrease of the productive capacity of land. Heavy metals are among the most dangerous pollutants because of their toxicity, persistent nature, easy up-take by plants and long biological half-life. This paper takes as its focus the study of crop species spectral response to Cd pollution. Ground-based experiments were performed, using alfalfa, spring barley and pea grown in Cd contaminated soils and in different hydroponic systems under varying concentrations of the heavy metal. Cd toxicity manifested itself by inhibition of plant growth and synthesis of photosynthetic pigments. Multispectral reflectance, absorbance and transmittance, as well as red and far red fluorescence were measured and examined for their suitability to detect differences in plant condition. Statistical analysis was performed and empirical relationships were established between Cd concentration, plant growth variables and spectral response Various spectral properties proved to be indicators of plant performance and quantitative estimators of the degree of the Cd-induced stress.

  4. Computational modeling of cardiovascular response to orthostatic stress

    NASA Technical Reports Server (NTRS)

    Heldt, Thomas; Shim, Eun B.; Kamm, Roger D.; Mark, Roger G.

    2002-01-01

    The objective of this study is to develop a model of the cardiovascular system capable of simulating the short-term (< or = 5 min) transient and steady-state hemodynamic responses to head-up tilt and lower body negative pressure. The model consists of a closed-loop lumped-parameter representation of the circulation connected to set-point models of the arterial and cardiopulmonary baroreflexes. Model parameters are largely based on literature values. Model verification was performed by comparing the simulation output under baseline conditions and at different levels of orthostatic stress to sets of population-averaged hemodynamic data reported in the literature. On the basis of experimental evidence, we adjusted some model parameters to simulate experimental data. Orthostatic stress simulations are not statistically different from experimental data (two-sided test of significance with Bonferroni adjustment for multiple comparisons). Transient response characteristics of heart rate to tilt also compare well with reported data. A case study is presented on how the model is intended to be used in the future to investigate the effects of post-spaceflight orthostatic intolerance.

  5. Circadian Rhythm and Stress Response in Droppings of Serinus canaria

    PubMed Central

    Turriani, Maura; Todisco, Gianluca; Montini, Luigi; Berardinelli, Paolo

    2016-01-01

    Serinus canaria is a widespread domestic ornamental songbird, whose limited knowledge of biology make compelling studies aimed to monitor stress. Here, a commercial enzyme immunoassay was adopted to measure immunoreactive corticosterone (CORT) in single Serinus canaria dropping sample, to monitor the daily fecal excretion of CORT in birds bred singly or in-group and to detect the effect promoted by aviary or small transport cage restraint. A robust daily rhythm of CORT was recorded in animals held on short-day light cycle, independent of bred conditions (single or group), which persisted when space availability was modified in single bred animal (transfer in aviary and transport cages). By contrast, a significant change in CORT excretion was recorded when group bred animals are restrained in a smaller cage. The daily rhythm in CORT excretion in response to manipulation showed the greatest response at the beginning of the light period, followed by the absence of the peak usually recorded at the end of the dark phase. These data indicated that EIA could be used as a reliable noninvasive approach to monitor the stress induced by restraint conditions in Serinus canaria. PMID:28105380

  6. RNA helicases: diverse roles in prokaryotic response to abiotic stress.

    PubMed

    Owttrim, George W

    2013-01-01

    Similar to proteins, RNA molecules must fold into the correct conformation and associate with protein complexes in order to be functional within a cell. RNA helicases rearrange RNA secondary structure and RNA-protein interactions in an ATP-dependent reaction, performing crucial functions in all aspects of RNA metabolism. In prokaryotes, RNA helicase activity is associated with roles in housekeeping functions including RNA turnover, ribosome biogenesis, translation and small RNA metabolism. In addition, RNA helicase expression and/or activity are frequently altered during cellular response to abiotic stress, implying they perform defined roles during cellular adaptation to changes in the growth environment. Specifically, RNA helicases contribute to the formation of cold-adapted ribosomes and RNA degradosomes, implying a role in alleviation of RNA secondary structure stabilization at low temperature. A common emerging theme involves RNA helicases acting as scaffolds for protein-protein interaction and functioning as molecular clamps, holding RNA-protein complexes in specific conformations. This review highlights recent advances in DEAD-box RNA helicase association with cellular response to abiotic stress in prokaryotes.

  7. Dual role of the integrated stress response in medulloblastoma tumorigenesis

    PubMed Central

    Li, Xiting; Jamison, Stephanie; Harding, Heather P.; Ron, David; Lin, Wensheng

    2016-01-01

    In response to endoplasmic reticulum (ER) stress, activation of pancreatic ER kinase (PERK) coordinates an adaptive program known as the integrated stress response (ISR) by phosphorylating translation initiation factor 2α (eIF2α). Phosphorylated eIF2α is quickly dephosphorylated by the protein phosphatase 1 and growth arrest and DNA damage 34 (GADD34) complex. Data indicate that the ISR can either promote or suppress tumor development. Our previous studies showed that the ISR is activated in medulloblastoma in both human patients and animal models, and that the decreased ISR via PERK heterozygous deficiency attenuates medulloblastoma formation in Patched1 heterozygous deficient (Ptch1+/−) mice by enhancing apoptosis of pre-malignant granule cell precursors (GCPs) during cell transformation. We showed here that GADD34 heterozygous mutation moderately enhanced the ISR and noticeably increased the incidence of medulloblastoma in adult Ptch1+/− mice. Surprisingly, GADD34 homozygous mutation strongly enhanced the ISR, but significantly decreased the incidence of medulloblastoma in adult Ptch1+/− mice. Intriguingly, GADD34 homozygous mutation significantly enhanced pre-malignant GCP apoptosis in cerebellar hyperplastic lesions and reduced the lesion numbers in young Ptch1+/− mice. Nevertheless, neither GADD34 heterozygous mutation nor GADD34 homozygous mutation had a significant effect on medulloblastoma cells in adult Ptch1+/− mice. Collectively, these data imply the dual role of the ISR, promoting and inhibiting, in medulloblastoma tumorigenesis by regulating apoptosis of pre-malignant GCPs during the course of malignant transformation. PMID:27802424

  8. Evaluating physiological responses of plants to salinity stress

    PubMed Central

    Negrão, S.; Schmöckel, S. M.; Tester, M.

    2017-01-01

    Background Because soil salinity is a major abiotic constraint affecting crop yield, much research has been conducted to develop plants with improved salinity tolerance. Salinity stress impacts many aspects of a plant’s physiology, making it difficult to study in toto. Instead, it is more tractable to dissect the plant’s response into traits that are hypothesized to be involved in the overall tolerance of the plant to salinity. Scope and conclusions We discuss how to quantify the impact of salinity on different traits, such as relative growth rate, water relations, transpiration, transpiration use efficiency, ionic relations, photosynthesis, senescence, yield and yield components. We also suggest some guidelines to assist with the selection of appropriate experimental systems, imposition of salinity stress, and obtaining and analysing relevant physiological data using appropriate indices. We illustrate how these indices can be used to identify relationships amongst the proposed traits to identify which traits are the most important contributors to salinity tolerance. Salinity tolerance is complex and involves many genes, but progress has been made in studying the mechanisms underlying a plant’s response to salinity. Nevertheless, several previous studies on salinity tolerance could have benefited from improved experimental design. We hope that this paper will provide pertinent information to researchers on performing proficient assays and interpreting results from salinity tolerance experiments. PMID:27707746

  9. 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

  10. Global SUMO Proteome Responses Guide Gene Regulation, mRNA Biogenesis, and Plant Stress Responses.

    PubMed

    Mazur, Magdalena J; van den Burg, Harrold A

    2012-01-01

    Small Ubiquitin-like MOdifier (SUMO) is a key regulator of abiotic stress, disease resistance, and development in plants. The identification of >350 plant SUMO targets has revealed many processes modulated by SUMO and potential consequences of SUMO on its targets. Importantly, highly related proteins are SUMO-modified in plants, yeast, and metazoans. Overlapping SUMO targets include heat-shock proteins (HSPs), transcription regulators, histones, histone-modifying enzymes, proteins involved in DNA damage repair, but also proteins involved in mRNA biogenesis and nucleo-cytoplasmic transport. Proteomics studies indicate key roles for SUMO in gene repression by controlling histone (de)acetylation activity at genomic loci. The responsible heavily sumoylated transcriptional repressor complexes are recruited by plant transcription factors (TFs) containing an (ERF)-associated Amphiphilic Repression (EAR) motif. These TFs are not necessarily themselves a SUMO target. Conversely, SUMO acetylation (Ac) prevents binding of downstream partners by blocking binding of their SUMO-interaction peptide motifs to Ac-SUMO. In addition, SUMO acetylation has emerged as a mechanism to recruit specifically bromodomains. Bromodomains are generally linked with gene activation. These findings strengthen the idea of a bi-directional sumo-acetylation switch in gene regulation. Quantitative proteomics has highlighted that global sumoylation provides a dynamic response to protein damage involving SUMO chain-mediated protein degradation, but also SUMO E3 ligase-dependent transcription of HSP genes. With these insights in SUMO function and novel technical advancements, we can now study SUMO dynamics in responses to (a)biotic stress in plants.

  11. Neural pathways link social support to attenuated neuroendocrine stress responses.

    PubMed

    Eisenberger, Naomi I; Taylor, Shelley E; Gable, Shelly L; Hilmert, Clayton J; Lieberman, Matthew D

    2007-05-01

    It is well established that a lack of social support constitutes a major risk factor for morbidity and mortality, comparable to risk factors such as smoking, obesity, and high blood pressure. Although it has been hypothesized that social support may benefit health by reducing physiological reactivity to stressors, the mechanisms underlying this process remain unclear. Moreover, to date, no studies have investigated the neurocognitive mechanisms that translate experiences of social support into the health outcomes that follow. To investigate these processes, thirty participants completed three tasks in which daily social support, neurocognitive reactivity to a social stressor, and neuroendocrine responses to a social stressor were assessed. Individuals who interacted regularly with supportive individuals across a 10-day period showed diminished cortisol reactivity to a social stressor. Moreover, greater social support and diminished cortisol responses were associated with diminished activity in the dorsal anterior cingulate cortex (dACC) and Brodmann's area (BA) 8, regions previously associated with the distress of social separation. Lastly, individual differences in dACC and BA 8 reactivity mediated the relationship between high daily social support and low cortisol reactivity, such that supported individuals showed reduced neurocognitive reactivity to social stressors, which in turn was associated with reduced neuroendocrine stress responses. This study is the first to investigate the neural underpinnings of the social support-health relationship and provides evidence that social support may ultimately benefit health by diminishing neural and physiological reactivity to social stressors.

  12. The Early Endocrine Stress Response in Experimental Subarachnoid Hemorrhage

    PubMed Central

    Nyberg, Christoffer; Karlsson, Torbjörn; Hillered, Lars; Stridsberg, Mats; Ronne Engström, Elisabeth

    2016-01-01

    Introduction In patients with severe illness, such as aneurysmal subarachnoid hemorrhage (SAH), a physiologic stress response is triggered. This includes activation of the hypothalamic-pituitary-adrenal (HPA) axis and the sympathetic nervous system. The aim of this study was to investigate the very early responses of these systems. Methods A porcine animal model of aneurysmal SAH was used. In this model, blood is injected slowly to the basal cisterns above the anterior skull base until the cerebral perfusion pressure is 0 mm Hg. Sampling was done from blood and urine at -10, +15, +75 and +135 minutes from time of induction of SAH. Analyses of adrenocorticotropic hormone (ACTH), cortisol, aldosterone, catecholamines and chromogranin-A were performed. Results Plasma ACTH, serum cortisol and plasma aldosterone increased in the samples following induction of SAH, and started to decline after 75 minutes. Urine cortisol also increased after SAH. Urine catecholamines and their metabolites were found to increase after SAH. Many samples were however below detection level, not allowing for statistical analysis. Plasma chromogranin-A peaked at 15 minutes after SAH, and thereafter decreased. Conclusions The endocrine stress response after aneurysmal SAH was found to start within 15 minutes in the HPA axis with early peak values of ACTH, cortisol and aldosterone. The fact that the concentrations of the HPA axis hormones decreased 135 minutes after SAH may suggest that a similar pattern exists in SAH patients, thus making it difficult to catch these early peak values. There were also indications of early activation of the sympathetic nervous system, but the small number of valid samples made interpretation difficult. PMID:27007694

  13. Proteomic Analysis of Trypanosoma cruzi Response to Ionizing Radiation Stress

    PubMed Central

    Vieira, Helaine Graziele Santos; Grynberg, Priscila; Bitar, Mainá; Pires, Simone da Fonseca; Hilário, Heron Oliveira; Macedo, Andrea Mara; Machado, Carlos Renato; de Andrade, Hélida Monteiro; Franco, Glória Regina

    2014-01-01

    Trypanosoma cruzi, the causative agent of Chagas disease, is extremely resistant to ionizing radiation, enduring up to 1.5 kGy of gamma rays. Ionizing radiation can damage the DNA molecule both directly, resulting in double-strand breaks, and indirectly, as a consequence of reactive oxygen species production. After a dose of 500 Gy of gamma rays, the parasite genome is fragmented, but the chromosomal bands are restored within 48 hours. Under such conditions, cell growth arrests for up to 120 hours and the parasites resume normal growth after this period. To better understand the parasite response to ionizing radiation, we analyzed the proteome of irradiated (4, 24, and 96 hours after irradiation) and non-irradiated T. cruzi using two-dimensional differential gel electrophoresis followed by mass spectrometry for protein identification. A total of 543 spots were found to be differentially expressed, from which 215 were identified. These identified protein spots represent different isoforms of only 53 proteins. We observed a tendency for overexpression of proteins with molecular weights below predicted, indicating that these may be processed, yielding shorter polypeptides. The presence of shorter protein isoforms after irradiation suggests the occurrence of post-translational modifications and/or processing in response to gamma radiation stress. Our results also indicate that active translation is essential for the recovery of parasites from ionizing radiation damage. This study therefore reveals the peculiar response of T. cruzi to ionizing radiation, raising questions about how this organism can change its protein expression to survive such a harmful stress. PMID:24842666

  14. Maternal Sensitivity and Infant Autonomic and Endocrine Stress Responses

    PubMed Central

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

    2014-01-01

    Background 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. Aims 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. Study Design Observational repeated measures study. Subjects Thirty-five urban, sociodemographically diverse mothers and their 6-month-old infants. Outcome Measures 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. Results 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. Conclusions 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. PMID:24794304

  15. Hormonal responses to psychological stress in men preparing for skydiving.

    PubMed

    Chatterton, R T; Vogelsong, K M; Lu, Y C; Hudgens, G A

    1997-08-01

    The purpose of the study was to examine the relationship between the hormonal and psychological responses of young men about to engage in a potentially life-threatening event. Subjects were recruited to take their first skydiving jump. The scores on questionnaires designed to assess anxiety were not significantly increased at 0800 h on the morning before the jump by comparison with scores obtained from the same subjects 3-5 days previously. However, a psychological instrument for rating of events indicated significantly increased intensity, and sympathetic nervous system activity, as measured by the salivary amylase response, was increased over self-control values. Salivary cortisol and testosterone levels were significantly lower on the morning of the jump than self-control values and values in control subjects determined at the same time of day. However, plasma LH was not suppressed. The anxiety and stress measures as well as the rating of events rose to high levels just before the jump. With the exception of testosterone, which remained low, serum cortisol, PRL, and GH all increased greatly subsequent to the rise in psychological measures, reached peak values before or shortly after landing, and declined significantly within the next hour. Anxiety and subjective stress scores declined to those of the self-control values within 15 min after landing, but the rating of events scale remained significantly elevated. In summary, reported anxiety associated with a purely psychological stressor was suppressed until within a few hours preceding the event, but was preceded by an increase in sympathetic nervous system activity and suppression of plasma cortisol and salivary testosterone levels. The event itself was associated with a reversal of the cortisol decline; other stress-associated hormones increased, but salivary testosterone remained low.

  16. Stress responsiveness predicts individual variation in mate selectivity.

    PubMed

    Vitousek, Maren N; Romero, L Michael

    2013-06-15

    Steroid hormones, including glucocorticoids, mediate a variety of behavioral and physiological processes. Circulating hormone concentrations vary substantially within populations, and although hormone titers predict reproductive success in several species, little is known about how individual variation in circulating hormone concentrations is linked with most reproductive behaviors in free-living organisms. Mate choice is an important and often costly component of reproduction that also varies substantially within populations. We examined whether energetically costly mate selection behavior in female Galápagos marine iguanas (Amblyrhynchus cristatus) was associated with individual variation in the concentrations of hormones previously shown to differ between reproductive and non-reproductive females during the breeding season (corticosterone and testosterone). Stress-induced corticosterone levels - which are suppressed in female marine iguanas during reproduction - were individually repeatable throughout the seven-week breeding period. Mate selectivity was strongly predicted by individual variation in stress-induced corticosterone: reproductive females that secreted less corticosterone in response to a standardized stressor assessed more displaying males. Neither baseline corticosterone nor testosterone predicted variation in mate selectivity. Scaled body mass was not significantly associated with mate selectivity, but females that began the breeding period in lower body condition showed a trend towards being less selective about potential mates. These results provide the first evidence that individual variation in the corticosterone stress response is associated with how selective females are in their choice of a mate, an important contributor to fitness in many species. Future research is needed to determine the functional basis of this association, and whether transient acute increases in circulating corticosterone directly mediate mate choice behaviors.

  17. Empathy and stress related neural responses in maternal decision making

    PubMed Central

    Ho, S. Shaun; Konrath, Sara; Brown, Stephanie; Swain, James E.

    2014-01-01

    Mothers need to make caregiving decisions to meet the needs of children, which may or may not result in positive child feedback. Variations in caregivers' emotional reactivity to unpleasant child-feedback may be partially explained by their dispositional empathy levels. Furthermore, empathic response to the child's unpleasant feedback likely helps mothers to regulate their own stress. We investigated the relationship between maternal dispositional empathy, stress reactivity, and neural correlates of child feedback to caregiving decisions. In Part 1 of the study, 33 female participants were recruited to undergo a lab-based mild stressor, the Social Evaluation Test (SET), and then in Part 2 of the study, a subset of the participants, 14 mothers, performed a Parenting Decision Making Task (PDMT) in an fMRI setting. Four dimensions of dispositional empathy based on the Interpersonal Reactivity Index were measured in all participants—Personal Distress, Empathic Concern, Perspective Taking, and Fantasy. Overall, we found that the Personal Distress and Perspective Taking were associated with greater and lesser cortisol reactivity, respectively. The four types of empathy were distinctly associated with the negative (vs. positive) child feedback activation in the brain. Personal Distress was associated with amygdala and hypothalamus activation, Empathic Concern with the left ventral striatum, ventrolateral prefrontal cortex (VLPFC), and supplemental motor area (SMA) activation, and Fantasy with the septal area, right SMA and VLPFC activation. Interestingly, hypothalamus-septal coupling during the negative feedback condition was associated with less PDMT-related cortisol reactivity. The roles of distinct forms of dispositional empathy in neural and stress responses are discussed. PMID:24971049

  18. Genomic Analysis of Stress Response against Arsenic in Caenorhabditis elegans

    PubMed Central

    Sahu, Surasri N.; Lewis, Jada; Patel, Isha; Bozdag, Serdar; Lee, Jeong H.; Sprando, Robert; Cinar, Hediye Nese

    2013-01-01

    Arsenic, a known human carcinogen, is widely distributed around the world and found in particularly high concentrations in certain regions including Southwestern US, Eastern Europe, India, China, Taiwan and Mexico. Chronic arsenic poisoning affects millions of people worldwide and is associated with increased risk of many diseases including arthrosclerosis, diabetes and cancer. In this study, we explored genome level global responses to high and low levels of arsenic exposure in Caenorhabditis elegans using Affymetrix expression microarrays. This experimental design allows us to do microarray analysis of dose-response relationships of global gene expression patterns. High dose (0.03%) exposure caused stronger global gene expression changes in comparison with low dose (0.003%) exposure, suggesting a positive dose-response correlation. Biological processes such as oxidative stress, and iron metabolism, which were previously reported to be involved in arsenic toxicity studies using cultured cells, experimental animals, and humans, were found to be affected in C. elegans. We performed genome-wide gene expression comparisons between our microarray data and publicly available C. elegans microarray datasets of cadmium, and sediment exposure samples of German rivers Rhine and Elbe. Bioinformatics analysis of arsenic-responsive regulatory networks were done using FastMEDUSA program. FastMEDUSA analysis identified cancer-related genes, particularly genes associated with leukemia, such as dnj-11, which encodes a protein orthologous to the mammalian ZRF1/MIDA1/MPP11/DNAJC2 family of ribosome-associated molecular chaperones. We analyzed the protective functions of several of the identified genes using RNAi. Our study indicates that C. elegans could be a substitute model to study the mechanism of metal toxicity using high-throughput expression data and bioinformatics tools such as FastMEDUSA. PMID:23894281

  19. Neuronal modelling of baroreflex response to orthostatic stress

    NASA Astrophysics Data System (ADS)

    Samin, Azfar

    The accelerations experienced in aerial combat can cause pilot loss of consciousness (GLOC) due to a critical reduction in cerebral blood circulation. The development of smart protective equipment requires understanding of how the brain processes blood pressure (BP) information in response to acceleration. We present a biologically plausible model of the Baroreflex to investigate the neural correlates of short-term BP control under acceleration or orthostatic stress. The neuronal network model, which employs an integrate-and-fire representation of a biological neuron, comprises the sensory, motor, and the central neural processing areas that form the Baroreflex. Our modelling strategy is to test hypotheses relating to the encoding mechanisms of multiple sensory inputs to the nucleus tractus solitarius (NTS), the site of central neural processing. The goal is to run simulations and reproduce model responses that are consistent with the variety of available experimental data. Model construction and connectivity are inspired by the available anatomical and neurophysiological evidence that points to a barotopic organization in the NTS, and the presence of frequency-dependent synaptic depression, which provides a mechanism for generating non-linear local responses in NTS neurons that result in quantifiable dynamic global baroreflex responses. The entire physiological range of BP and rate of change of BP variables is encoded in a palisade of NTS neurons in that the spike responses approximate Gaussian 'tuning' curves. An adapting weighted-average decoding scheme computes the motor responses and a compensatory signal regulates the heart rate (HR). Model simulations suggest that: (1) the NTS neurons can encode the hydrostatic pressure difference between two vertically separated sensory receptor regions at +Gz, and use changes in that difference for the regulation of HR; (2) even though NTS neurons do not fire with a cardiac rhythm seen in the afferents, pulse

  20. Mesolimbic neuropeptide W coordinates stress responses under novel environments.

    PubMed

    Motoike, Toshiyuki; Long, Jeffrey M; Tanaka, Hirokazu; Sinton, Christopher M; Skach, Amber; Williams, S Clay; Hammer, Robert E; Sakurai, Takeshi; Yanagisawa, Masashi

    2016-05-24

    Neuropeptide B (NPB) and neuropeptide W (NPW) are endogenous neuropeptide ligands for the G protein-coupled receptors NPBWR1 and NPBWR2. Here we report that the majority of NPW neurons in the mesolimbic region possess tyrosine hydroxylase immunoreactivity, indicating that a small subset of dopaminergic neurons coexpress NPW. These NPW-containing neurons densely and exclusively innervate two limbic system nuclei in adult mouse brain: the lateral bed nucleus of the stria terminalis and the lateral part of the central amygdala nucleus (CeAL). In the CeAL of wild-type mice, restraint stress resulted in an inhibition of cellular activity, but this stress-induced inhibition was attenuated in the CeAL neurons of NPW(-/-) mice. Moreover, the response of NPW(-/-) mice to either formalin-induced pain stimuli or a live rat (i.e., a potential predator) was abnormal only when they were placed in a novel environment: The mice failed to show the normal species-specific self-protective and aversive reactions. In contrast, the behavior of NPW(-/-) mice in a habituated environment was indistinguishable from that of wild-type mice. These results indicate that the NPW/NPBWR1 system could play a critical role in the gating of stressful stimuli during exposure to novel environments.

  1. Population differences in response to hypoxic stress in Atlantic salmon.

    PubMed

    Côte, J; Roussel, J-M; Le Cam, S; Bal, G; Evanno, G

    2012-12-01

    Understanding whether populations can adapt to new environmental conditions is a major issue in conservation and evolutionary biology. Aquatic organisms are increasingly exposed to environmental changes linked with human activities in river catchments. For instance, the clogging of bottom substratum by fine sediments is observed in many rivers and usually leads to a decrease in dissolved oxygen concentrations in gravel beds. Such hypoxic stress can alter the development and even be lethal for Atlantic salmon (Salmo salar) embryos that spend their early life into gravel beds. In this study, we used a common garden experiment to compare the responses to hypoxic stress of four genetically differentiated and environmentally contrasted populations. We used factorial crossing designs to measure additive genetic variation of early life-history traits in each population. Embryos were reared under normoxic and hypoxic conditions, and we measured their survival, incubation time and length at the end of embryonic development. Under hypoxic conditions, embryos had a lower survival and hatched later than in normoxic conditions. We found different hypoxia reaction norms among populations, but almost no population effect in both treatments. We also detected significant sire × treatment interactions in most populations and a tendency for heritability values to be lower under stressful conditions. Overall, these results reveal a high degree of phenotypic plasticity in salmon populations that nevertheless differ in their adaptive potential to hypoxia given the distinct reaction norms observed between and within populations.

  2. L-Theanine reduces psychological and physiological stress responses.

    PubMed

    Kimura, Kenta; Ozeki, Makoto; Juneja, Lekh Raj; Ohira, Hideki

    2007-01-01

    L-Theanine is an amino acid contained in green tea leaves which is known to block the binding of L-glutamic acid to glutamate receptors in the brain. Because the characteristics of L-Theanine suggest that it may influence psychological and physiological states under stress, the present study examined these possible effects in a laboratory setting using a mental arithmetic task as an acute stressor. Twelve participants underwent four separate trials: one in which they took L-Theanine at the start of an experimental procedure, one in which they took L-Theanine midway, and two control trials in which they either took a placebo or nothing. The experimental sessions were performed by double-blind, and the order of them was counterbalanced. The results showed that L-Theanine intake resulted in a reduction in the heart rate (HR) and salivary immunoglobulin A (s-IgA) responses to an acute stress task relative to the placebo control condition. Moreover, analyses of heart rate variability indicated that the reductions in HR and s-IgA were likely attributable to an attenuation of sympathetic nervous activation. Thus, it was suggested that the oral intake of L-Theanine could cause anti-stress effects via the inhibition of cortical neuron excitation.

  3. Stress and adaptation responses to repeated acute acceleration.

    NASA Technical Reports Server (NTRS)

    Burton, R. R.; Smith, A. H.

    1972-01-01

    Study in which groups of adult male chickens (single-comb white leghorn) were exposed daily to acceleration (centrifugation) of 2 or 3 G for 10 min, 1, 4, 8, 12, 16, and 24 hr (continuously), or 0 time (controls). After approximately five months of this intermittent treatment (training), the birds were exposed to continuous accelerations of the same G force (intensity). The degree of stress and adaptation of each bird was determined by survival and relative lymphocyte count criteria. Intermittent training exposures of 2 G developed levels of adaptation in birds directly proportional to the duration of their daily exposure. Intermittent training periods at 3 G, however, produced a physiological deterioration in birds receiving daily exposures of 8 hr or more. Adaptive benefits were found only in the 1- and 4-hr-daily intermittent 3-G exposure groups. Exposure to 3 G produced an immediate stress response as indicated by a low relative lymphocyte count which returned to control (preexposed) values prior to the next daily acceleration period in the 10-min, 1-hr, and 4-hr groups. This daily recovery period from stress appeared to be necessary for adaptation as opposed to deterioration for the more severe environmental (3 G) alteration.

  4. Increased oxidative stress and impaired antioxidant response in Lafora disease.

    PubMed

    Romá-Mateo, Carlos; Aguado, Carmen; García-Giménez, José Luis; Ibáñez-Cabellos, José Santiago; Seco-Cervera, Marta; Pallardó, Federico V; Knecht, Erwin; Sanz, Pascual

    2015-01-01

    Lafora disease (LD, OMIM 254780, ORPHA501) is a fatal neurodegenerative disorder characterized by the presence of glycogen-like intracellular inclusions called Lafora bodies and caused, in the vast majority of cases, by mutations in either EPM2A or EPM2B genes, encoding respectively laforin and malin. In the last years, several reports have revealed molecular details of these two proteins and have identified several processes affected in LD, but the pathophysiology of the disease still remains largely unknown. Since autophagy impairment has been reported as a characteristic treat in both Lafora disease cell and animal models, and as there is a link between autophagy and mitochondrial performance, we sought to determine if mitochondrial function could be altered in those models. Using fibroblasts from LD patients, deficient in laforin or malin, we found mitochondrial alterations, oxidative stress and a deficiency in antioxidant enzymes involved in the detoxification of reactive oxygen species (ROS). Similar results were obtained in brain tissue samples from transgenic mice deficient in either the EPM2A or EPM2B genes. Furthermore, in a proteomic analysis of brain tissue obtained from Epm2b-/- mice, we observed an increase in a modified form of peroxiredoxin-6, an antioxidant enzyme involved in other neurological pathologies, thus corroborating an alteration of the redox condition. These data support that oxidative stress produced by an increase in ROS production and an impairment of the antioxidant enzyme response to this stress play an important role in development of LD.

  5. Molecular and physiological responses of trees to waterlogging stress.

    PubMed

    Kreuzwieser, Jürgen; Rennenberg, Heinz

    2014-10-01

    One major effect of global climate change will be altered precipitation patterns in many regions of the world. This will cause a higher probability of long-term waterlogging in winter/spring and flash floods in summer because of extreme rainfall events. Particularly, trees not adapted at their natural site to such waterlogging stress can be impaired. Despite the enormous economic, ecological and social importance of forest ecosystems, the effect of waterlogging on trees is far less understood than the effect on many crops or the model plant Arabidopsis. There is only a handful of studies available investigating the transcriptome and metabolome of waterlogged trees. Main physiological responses of trees to waterlogging include the stimulation of fermentative pathways and an accelerated glycolytic flux. Many energy-consuming, anabolic processes are slowed down to overcome the energy crisis mediated by waterlogging. A crucial feature of waterlogging tolerance is the steady supply of glycolysis with carbohydrates, particularly in the roots; stress-sensitive trees fail to maintain sufficient carbohydrate availability resulting in the dieback of the stressed tissues. The present review summarizes physiological and molecular features of waterlogging tolerance of trees; the focus is on carbon metabolism in both, leaves and roots of trees.

  6. Linking physiological and cellular responses to thermal stress: β-adrenergic blockade reduces the heat shock response in fish.

    PubMed

    Templeman, Nicole M; LeBlanc, Sacha; Perry, Steve F; Currie, Suzanne

    2014-08-01

    When faced with stress, animals use physiological and cellular strategies to preserve homeostasis. We were interested in how these high-level stress responses are integrated at the level of the whole animal. Here, we investigated the capacity of the physiological stress response, and specifically the β-adrenergic response, to affect the induction of the cellular heat shock proteins, HSPs, following a thermal stress in vivo. We predicted that blocking β-adrenergic stimulation during an acute heat stress in the whole animal would result in reduced levels of HSPs in red blood cells (RBCs) of rainbow trout compared to animals where adrenergic signaling remained intact. We first determined that a 1 h heat shock at 25 °C in trout acclimated to 13 °C resulted in RBC adrenergic stimulation as determined by a significant increase in cell swelling, a hallmark of the β-adrenergic response. A whole animal injection with the β2-adrenergic antagonist, ICI-118,551, successfully reduced this heat-induced RBC swelling. The acute heat shock caused a significant induction of HSP70 in RBCs of 13 °C-acclimated trout as well as a significant increase in plasma catecholamines. When heat-shocked fish were treated with ICI-118,551, we observed a significant attenuation of the HSP70 response. We conclude that circulating catecholamines influence the cellular heat shock response in rainbow trout RBCs, demonstrating physiological/hormonal control of the cellular stress response.

  7. Role of counterregulatory hormones in the catabolic response to stress.

    PubMed Central

    Gelfand, R A; Matthews, D E; Bier, D M; Sherwin, R S

    1984-01-01

    Patients with major injury or illness develop protein wasting, hypermetabolism, and hyperglycemia with increased glucose flux. To assess the role of elevated counterregulatory hormones in this response, we simultaneously infused cortisol (6 mg/m2 per h), glucagon (4 ng/kg per min), epinephrine (0.6 microgram/m2 per min), and norepinephrine (0.8 micrograms/m2 per min) for 72 h into five obese subjects receiving only intravenous glucose (150 g/d). Four obese subjects received cortisol alone under identical conditions. Combined infusion maintained plasma hormone elevations typical of severe stress for 3 d. This caused a sustained increase in plasma glucose (60-80%), glucose production (100%), and total glucose flux (40%), despite persistent hyperinsulinemia. In contrast, resting metabolic rate changed little (9% rise, P = NS). Urinary nitrogen excretion promptly doubled and remained increased by approximately 4 g/d, reflecting increased excretion of urea and ammonia. Virtually all plasma amino acids declined. The increment in nitrogen excretion was similar in three additional combined infusion studies performed in 3-d fasted subjects not receiving glucose. Cortisol alone produced a smaller glycemic response (20-25%), an initially smaller insulin response, and a delayed rise in nitrogen excretion. By day 3, however, daily nitrogen excretion was equal to the combined group as was the elevation in plasma insulin. Most plasma amino acids rose rather than fell. In both infusion protocols nitrogen wasting was accompanied by only modest increments in 3-methylhistidine excretion (approximately 20-30%) and no significant change in leucine flux. We conclude: (a) Prolonged elevations of multiple stress hormones cause persistent hyperglycemia, increased glucose turnover, and increased nitrogen loss; (b) The sustained nitrogen loss is no greater than that produced by cortisol alone; (c) Glucagon, epinephrine, and norepinephrine transiently augment cortisol-induced nitrogen loss

  8. Ascending mechanisms of stress integration: Implications for brainstem regulation of neuroendocrine and behavioral stress responses.

    PubMed

    Myers, Brent; Scheimann, Jessie R; Franco-Villanueva, Ana; Herman, James P

    2017-03-01

    In response to stress, defined as a real or perceived threat to homeostasis or well-being, brain systems initiate divergent physiological and behavioral processes that mobilize energy and promote adaptation. The brainstem contains multiple nuclei that engage in autonomic control and reflexive responses to systemic stressors. However, brainstem nuclei also play an important role in neuroendocrine responses to psychogenic stressors mediated by the hypothalamic-pituitary-adrenocortical axis. Further, these nuclei integrate neuroendocrine responses with stress-related behaviors, significantly impacting mood and anxiety. The current review focuses on the prominent brainstem monosynaptic inputs to the endocrine paraventricular hypothalamic nucleus (PVN), including the periaqueductal gray, raphe nuclei, parabrachial nuclei, locus coeruleus, and nucleus of the solitary tract (NTS). The NTS is a particularly intriguing area, as the region contains multiple cell groups that provide neurochemically-distinct inputs to the PVN. Furthermore, the NTS, under regulatory control by glucocorticoid-mediated feedback, integrates affective processes with physiological status to regulate stress responding. Collectively, these brainstem circuits represent an important avenue for delineating interactions between stress and health.

  9. Does heat stress alter the pig's response to dietary fat?

    PubMed

    Kellner, T A; Baumgard, L H; Prusa, K J; Gabler, N K; Patience, J F

    2016-11-01

    Heat stress (HS) results in major losses to the pork industry via reduced growth performance and, possibly, carcass fat quality. The experimental objective was to measure the effects of HS on the pig's response to dietary fat in terms of lipid digestion, metabolism, and deposition over a 35-d finishing period. A total of 96 PIC 337 × C22/C29 (PIC, Inc., Hendersonville, TN) barrows (initial BW of 100.4 ± 1.2 kg) were randomly allotted to 1 of 9 treatments arranged as a 3 × 3 factorial: thermoneutral (TN; constant 24°C; ad libitum access to feed), pair-fed thermoneutral (PFTN; constant 24°C; limit fed based on previous HS daily feed intake), or HS (cyclical 28°C nighttime, 33°C from d 0 to 7, 33.5°C from d 7 to 14, 34°C from d 14 to 21, 34.5°C from d 21 to 28, and 35°C from d 28 to 35 daytime; ab libitum access to feed) and diet (a corn-soybean meal-based diet with 0% added fat [CNTR], CNTR with 3% added tallow [TAL; iodine value {IV} = 41.8], or CNTR with 3% added corn oil [CO; IV = 123.0]). No interactions between environment and diet were evident for any major response criteria ( ≥ 0.063). Rectal temperature increased due to HS (39.0°C for HS, 38.1°C for TN, and 38.2°C for PFTN; < 0.001). Heat stress decreased ADFI (27.8%; < 0.001), ADG (0.72 kg/d for HS, 1.03 kg/d for TN, and 0.78 kg/d for PFTN; < 0.001), and G:F (0.290 for HS, 0.301 for TN, and 0.319 for PFTN; = 0.006). Heat stress barrows required 1.2 Mcal of ME intake more per kilogram of BW gain than PFTN ( < 0.001). Heat stress tended to result in the lowest apparent total tract digestibility of acid hydrolyzed ether extract (AEE; 59.0% for HS, 60.2% for TN, and 61.4% for PFTN; = 0.055). True total tract digestibility (TTTD) of AEE of CO-based diets (99.3%) was greater than that of CNTR (97.3%) and TAL-based diets (96.3%; = 0.012). Environment had no impact on TTTD of AEE ( = 0.118). Environment had no impact on jowl IV at market (69.2 g/100 g for HS, 69.3 g/100 g for TN, and 69.8 g/100 g for

  10. How are neuroticism and depression related to the psychophysiological stress response to acute stress in healthy older people?

    PubMed

    Puig-Perez, Sara; Villada, Carolina; Pulopulos, Matias M; Hidalgo, Vanesa; Salvador, Alicia

    2016-03-15

    Neuroticism and depressive symptomatology have been related to a heightened and diminished physiological stress response, which may partly explain their negative relationship with health and wellbeing. Identifying factors that may increase disease vulnerability is especially relevant in older people, whose physiological systems decline. With this in mind, we investigated the influence of neuroticism and depression on the psychophysiological stress response in healthy older people (from 55 to 76years old). A total of 36 volunteers were exposed to a stressful task (Trier Social Stress Test, TSST), while 35 volunteers performed a control non-stressful task. The physiological stress response was assessed through measures of cortisol, alpha-amylase, heart rate (HR). Our results showed that, neuroticism was not related to physiological stress response. However, depression was related to higher cortisol response and lower HR reactivity in the stress condition. In summary, emotional states such as depressive mood seem to amplify the cortisol stress response and reduce the cardiovascular response, whereas more stable dispositions such as neuroticism did not affect stress response in older people. These findings confirm, in healthy older people, the adverse effects of depression, acting on different subsystems of the stress response.

  11. NEURONATIN IS A STRESS-RESPONSIVE PROTEIN OF ROD PHOTORECEPTORS

    PubMed Central

    SHINDE, VISHAL; PITALE, PRIYAMVADA M.; HOWSE, WAYNE; GORBATYUK, OLEG; GORBATYUK, MARINA

    2016-01-01

    Neuronatin (NNAT) is a small transmembrane proteolipid that is highly expressed in the embryonic developing brain and several other peripheral tissues. This study is the first to provide evidence that NNAT is detected in the adult retina of various adult rod-dominant mammals, including wild-type (WT) rodents, transgenic rodents expressing mutant S334ter, P23H, or T17M rhodopsin, non-human primates, humans, and cone-dominant tree shrews. Immunohistochemical and quantitative real time polymerase chain reaction (qRT-PCR) analyses were applied to detect NNAT. Confocal microscopy analysis revealed that NNAT immunofluorescence is restricted to the outer segments (OSs) of photoreceptors without evidence of staining in other retinal cell types across all mammalian species. Moreover, in tree shrew retinas, we found NNAT to be co-localized with rhodopsin, indicating its predominant expression in rods. The rod-derived expression of NNAT was further confirmed by qRT-PCR in isolated rod photoreceptor cells. We also used these cells to mimic cellular stress in transgenic retinas by treating them with the endoplasmic reticulum stress inducer, tunicamycin. Thus, our data revealed accumulation of NNAT around the nucleus as compared to dispersed localization of NNAT within control cells. This distribution coincided with the partial intracellular mislocalization of NNAT to the outer nuclear layer observed in transgenic retinas. In addition, stressed retinas demonstrated an increase of NNAT mRNA and protein levels. Therefore, our study demonstrated that NNAT is a novel stress-responsive protein with a potential structural and/or functional role in adult mammalian retinas. PMID:27109921

  12. Response of spermatozoa to hyposmotic stress reflects cryopreservation success

    SciTech Connect

    Watson, P.F.; Curry, M.R.; Noiles, E.E.; Critser, J.K.; Mazur, P.; Hammerstedt, R.H.

    1992-06-01

    Spermatozoa of several species were washed and then subjected to dilution in hyposmotic Tyrode`s based solutions. The cells were stained with fluorescent viability stains, carboxyfluorescein diacetate and propidium iodide, and proportions with intact plasma membranes determined by flow cytometry or fluorescence microscopy. Fowl spermatozoa remained almost 100% intact until very low osmolality, and then ruptured. Human spermatozoa showed a similar response with only a small decrease in intact cells before the precipitous decline at low osmolality. Bull spermatozoa were more readily disrupted at higher osmolality, some 40% being damaged before the sudden decline at low osmolality. Ram and boar spermatozoa were progressively disrupted even at mild hyposmotic stress, showing approximately 50% of cells ruptured at 150 mOsm.

  13. Response of spermatozoa to hyposmotic stress reflects cryopreservation success

    SciTech Connect

    Watson, P.F.; Curry, M.R. ); Noiles, E.E.; Critser, J.K. . Center for Reproduction); Mazur, P. ); Hammerstedt, R.H. . Dept. of Cellular and Molecular B

    1992-01-01

    Spermatozoa of several species were washed and then subjected to dilution in hyposmotic Tyrode's based solutions. The cells were stained with fluorescent viability stains, carboxyfluorescein diacetate and propidium iodide, and proportions with intact plasma membranes determined by flow cytometry or fluorescence microscopy. Fowl spermatozoa remained almost 100% intact until very low osmolality, and then ruptured. Human spermatozoa showed a similar response with only a small decrease in intact cells before the precipitous decline at low osmolality. Bull spermatozoa were more readily disrupted at higher osmolality, some 40% being damaged before the sudden decline at low osmolality. Ram and boar spermatozoa were progressively disrupted even at mild hyposmotic stress, showing approximately 50% of cells ruptured at 150 mOsm.

  14. The stress-vulnerability hypothesis in psychotic disorders: focus on the stress response systems.

    PubMed

    Gispen-de Wied, Christine C; Jansen, Lucres M C

    2002-06-01

    The vulnerabilty stress model is an intriguing concept to look into the etiology of psychotic disorders and, in particular, into the "nature nurture" principle. That stress affects a vulnerable nature may be obvious, but its mechanism is not well understood, and many questions remain to be answered, let alone how to define "vulnerability". The present review tries to focus on the core issues of the vulnerability stress concept--identifying vulnerability, the way stress interferes with it, and the possiblilities of modulating their interaction. Attention is drawn to the biologic stress response systems, the autonomic nervous system (ANS), the hypothalamic pituitary adrenal (HPA) system, and the immune system, and highlights the plasticity of the HPA system as the mediator of adaptation.

  15. Improving alkenone paleothermometry by incorporating cell response to environmental stress

    NASA Astrophysics Data System (ADS)

    Prahl, F. G.; Wolfe, G. V.; Mix, A. C.; Sparrow, M. A.

    2003-04-01

    A linear, global coretop calibration now exists for the alkenone unsaturation index Uk’37 and mean annual SST (maSST). The calibration equation is statistically the same as that for a subarctic Pacific strain of Emiliania huxleyi (Ehux) grown exponentially under isothermal conditions in batch culture. Although the calibration has been applied widely for paleoSST reconstruction, uncertainty still exists, stemming from two key factors: genetic variability among strains, and physiologic response to stress and growth state. We will discuss in this talk the extent that Uk’37 and other aspects of cellular alkenone composition vary in response to nutrient depletion and light deprivation in isothermal (15^oC) batch cultures of Ehux isolated from three different ocean locations - a Norwegian fjord (CCMP370); the subarctic Pacific (CCMP1742) and the Sargasso Sea (CCMP 372). We will also present results from detailed alkenone compositional analysis in thirty surface sediments collected between ˜50^oS and 10^oS along the Chile-Peru margin in the SE Pacific Ocean. The Uk’37 - maSST relationship derived from this dataset is statistically indistinguishable from the global coretop calibration. But, comparison of other compositional properties shows that the alkenone signature preserved in the Chile-Peru margin sediments is also not consistent with that expressed by exponentially growing cells of any of the three cultured Ehux strains. Alkenone signatures preserved in sediments appear more like that in algal cells that have experienced some level of non-thermal, physiological stress such as nutrient and light limitation. Given our observations as a precedent, improved confidence in paleotemperature estimates derived from Uk’37 measurements may require interpretation of unsaturation patterns in full context with the overall alkenone composition preserved in the sediment.

  16. Key Role of CRF in the Skin Stress Response System

    PubMed Central

    Zmijewski, Michal A.; Zbytek, Blazej; Tobin, Desmond J.; Theoharides, Theoharis C.; Rivier, Jean

    2013-01-01

    The discovery of corticotropin-releasing factor (CRF) or CRH defining the upper regulatory arm of the hypothalamic-pituitary-adrenal (HPA) axis, along with the identification of the corresponding receptors (CRFRs 1 and 2), represents a milestone in our understanding of central mechanisms regulating body and local homeostasis. We focused on the CRF-led signaling systems in the skin and offer a model for regulation of peripheral homeostasis based on the interaction of CRF and the structurally related urocortins with corresponding receptors and the resulting direct or indirect phenotypic effects that include regulation of epidermal barrier function, skin immune, pigmentary, adnexal, and dermal functions necessary to maintain local and systemic homeostasis. The regulatory modes of action include the classical CRF-led cutaneous equivalent of the central HPA axis, the expression and function of CRF and related peptides, and the stimulation of pro-opiomelanocortin peptides or cytokines. The key regulatory role is assigned to the CRFR-1α receptor, with other isoforms having modulatory effects. CRF can be released from sensory nerves and immune cells in response to emotional and environmental stressors. The expression sequence of peptides includes urocortin/CRF→pro-opiomelanocortin→ACTH, MSH, and β-endorphin. Expression of these peptides and of CRFR-1α is environmentally regulated, and their dysfunction can lead to skin and systemic diseases. Environmentally stressed skin can activate both the central and local HPA axis through either sensory nerves or humoral factors to turn on homeostatic responses counteracting cutaneous and systemic environmental damage. CRF and CRFR-1 may constitute novel targets through the use of specific agonists or antagonists, especially for therapy of skin diseases that worsen with stress, such as atopic dermatitis and psoriasis. PMID:23939821

  17. Key role of CRF in the skin stress response system.

    PubMed

    Slominski, Andrzej T; Zmijewski, Michal A; Zbytek, Blazej; Tobin, Desmond J; Theoharides, Theoharis C; Rivier, Jean

    2013-12-01

    The discovery of corticotropin-releasing factor (CRF) or CRH defining the upper regulatory arm of the hypothalamic-pituitary-adrenal (HPA) axis, along with the identification of the corresponding receptors (CRFRs 1 and 2), represents a milestone in our understanding of central mechanisms regulating body and local homeostasis. We focused on the CRF-led signaling systems in the skin and offer a model for regulation of peripheral homeostasis based on the interaction of CRF and the structurally related urocortins with corresponding receptors and the resulting direct or indirect phenotypic effects that include regulation of epidermal barrier function, skin immune, pigmentary, adnexal, and dermal functions necessary to maintain local and systemic homeostasis. The regulatory modes of action include the classical CRF-led cutaneous equivalent of the central HPA axis, the expression and function of CRF and related peptides, and the stimulation of pro-opiomelanocortin peptides or cytokines. The key regulatory role is assigned to the CRFR-1α receptor, with other isoforms having modulatory effects. CRF can be released from sensory nerves and immune cells in response to emotional and environmental stressors. The expression sequence of peptides includes urocortin/CRF→pro-opiomelanocortin→ACTH, MSH, and β-endorphin. Expression of these peptides and of CRFR-1α is environmentally regulated, and their dysfunction can lead to skin and systemic diseases. Environmentally stressed skin can activate both the central and local HPA axis through either sensory nerves or humoral factors to turn on homeostatic responses counteracting cutaneous and systemic environmental damage. CRF and CRFR-1 may constitute novel targets through the use of specific agonists or antagonists, especially for therapy of skin diseases that worsen with stress, such as atopic dermatitis and psoriasis.

  18. Dynamic involvement of ATG5 in cellular stress responses

    PubMed Central

    Lin, H H; Lin, S-M; Chung, Y; Vonderfecht, S; Camden, J M; Flodby, P; Borok, Z; Limesand, K H; Mizushima, N; Ann, D K

    2014-01-01

    Autophagy maintains cell and tissue homeostasis through catabolic degradation. To better delineate the in vivo function for autophagy in adaptive responses to tissue injury, we examined the impact of compromised autophagy in mouse submandibular glands (SMGs) subjected to main excretory duct ligation. Blocking outflow from exocrine glands causes glandular atrophy by increased ductal pressure. Atg5f/−;Aqp5-Cre mice with salivary acinar-specific knockout (KO) of autophagy essential gene Atg5 were generated. While duct ligation induced autophagy and the expression of inflammatory mediators, SMGs in Atg5f/−;Aqp5-Cre mice, before ligation, already expressed higher levels of proinflammatory cytokine and Cdkn1a/p21 messages. Extended ligation period resulted in the caspase-3 activation and acinar cell death, which was delayed by Atg5 knockout. Moreover, expression of a set of senescence-associated secretory phenotype (SASP) factors was elevated in the post-ligated glands. Dysregulation of cell-cycle inhibitor CDKN1A/p21 and activation of senescence-associated β-galactosidase were detected in the stressed SMG duct cells. These senescence markers peaked at day 3 after ligation and partially resolved by day 7 in post-ligated SMGs of wild-type (WT) mice, but not in KO mice. The role of autophagy-related 5 (ATG5)-dependent autophagy in regulating the tempo, duration and magnitude of cellular stress responses in vivo was corroborated by in vitro studies using MEFs lacking ATG5 or autophagy-related 7 (ATG7) and autophagy inhibitors. Collectively, our results highlight the role of ATG5 in the dynamic regulation of ligation-induced cellular senescence and apoptosis, and suggest the involvement of autophagy resolution in salivary repair. PMID:25341032

  19. Saccharomyces cerevisiae Tti2 Regulates PIKK Proteins and Stress Response

    PubMed Central

    Hoffman, Kyle S.; Duennwald, Martin L.; Karagiannis, Jim; Genereaux, Julie; McCarton, Alexander S.; Brandl, Christopher J.

    2016-01-01

    The TTT complex is composed of the three essential proteins Tel2, Tti1, and Tti2. The complex is required to maintain steady state levels of phosphatidylinositol 3-kinase-related kinase (PIKK) proteins, including mTOR, ATM/Tel1, ATR/Mec1, and TRRAP/Tra1, all of which serve as regulators of critical cell signaling pathways. Due to their association with heat shock proteins, and with newly synthesized PIKK peptides, components of the TTT complex may act as cochaperones. Here, we analyze the consequences of depleting the cellular level of Tti2 in Saccharomyces cerevisiae. We show that yeast expressing low levels of Tti2 are viable under optimal growth conditions, but the cells are sensitive to a number of stress conditions that involve PIKK pathways. In agreement with this, depleting Tti2 levels decreased expression of Tra1, Mec1, and Tor1, affected their localization and inhibited the stress responses in which these molecules are involved. Tti2 expression was not increased during heat shock, implying that it does not play a general role in the heat shock response. However, steady state levels of Hsp42 increase when Tti2 is depleted, and tti2L187P has a synthetic interaction with exon 1 of the human Huntingtin gene containing a 103 residue polyQ sequence, suggesting a general role in protein quality control. We also find that overexpressing Hsp90 or its cochaperones is synthetic lethal when Tti2 is depleted, an effect possibly due to imbalanced stoichiometry of a complex required for PIKK assembly. These results indicate that Tti2 does not act as a general chaperone, but may have a specialized function in PIKK folding and/or complex assembly. PMID:27172216

  20. Phosphorus stress in common bean: root transcript and metabolic responses.

    PubMed

    Hernández, Georgina; Ramírez, Mario; Valdés-López, Oswaldo; Tesfaye, Mesfin; Graham, Michelle A; Czechowski, Tomasz; Schlereth, Armin; Wandrey, Maren; Erban, Alexander; Cheung, Foo; Wu, Hank C; Lara, Miguel; Town, Christopher D; Kopka, Joachim; Udvardi, Michael K; Vance, Carroll P

    2007-06-01

    Phosphorus (P) is an essential element for plant growth. Crop production of common bean (Phaseolus vulgaris), the most important legume for human consumption, is often limited by low P in the soil. Functional genomics were used to investigate global gene expression and metabolic responses of bean plants grown under P-deficient and P-sufficient conditions. P-deficient plants showed enhanced root to shoot ratio accompanied by reduced leaf area and net photosynthesis rates. Transcript profiling was performed through hybridization of nylon filter arrays spotted with cDNAs of 2,212 unigenes from a P deficiency root cDNA library. A total of 126 genes, representing different functional categories, showed significant differential expression in response to P: 62% of these were induced in P-deficient roots. A set of 372 bean transcription factor (TF) genes, coding for proteins with Inter-Pro domains characteristic or diagnostic for TF, were identified from The Institute of Genomic Research/Dana Farber Cancer Institute Common Bean Gene Index. Using real-time reverse transcription-polymerase chain reaction analysis, 17 TF genes were differentially expressed in P-deficient roots; four TF genes, including MYB TFs, were induced. Nonbiased metabolite profiling was used to assess the degree to which changes in gene expression in P-deficient roots affect overall metabolism. Stress-related metabolites such as polyols accumulated in P-deficient roots as well as sugars, which are known to be essential for P stress gene induction. Candidate genes have been identified that may contribute to root adaptation to P deficiency and be useful for improvement of common bean.

  1. Transcriptome analysis of molecular mechanisms responsible for light-stress response in Mythimna separata (Walker).

    PubMed

    Duan, Yun; Gong, ZhongJun; Wu, RenHai; Miao, Jin; Jiang, YueLi; Li, Tong; Wu, XiaoBo; Wu, YuQing

    2017-03-27

    Light is an important environmental signal for most insects. The Oriental Armyworm, Mythimna separata, is a serious pest of cereal crops worldwide, and is highly sensitive to light signals during its developmental and reproductive stages. However, molecular biological studies of its response to light stress are scarce, and related genomic information is not available. In this study, we sequenced and de novo assembled the transcriptomes of M. separata exposed to four different light conditions: dark, white light (WL), UV light (UVL) and yellow light (YL). A total of 46,327 unigenes with an average size of 571 base pairs (bp) were obtained, among which 24,344 (52.55%) matched to public databases. The numbers of genes differentially expressed between dark vs WL, dark vs UVL, dark vs YL, and UVL vs YL were 12,012, 12,950, 14,855, and 13,504, respectively. These results suggest that light exposure altered gene expression patterns in M. separata. Putative genes involved in phototransduction-fly, phototransduction, circadian rhythm-fly, olfactory transduction, and taste transduction were identified. This study thus identified a series of candidate genes and pathways potentially related to light stress in M. separata.

  2. Transcriptome analysis of molecular mechanisms responsible for light-stress response in Mythimna separata (Walker)

    PubMed Central

    Duan, Yun; Gong, ZhongJun; Wu, RenHai; Miao, Jin; Jiang, YueLi; Li, Tong; Wu, XiaoBo; Wu, YuQing

    2017-01-01

    Light is an important environmental signal for most insects. The Oriental Armyworm, Mythimna separata, is a serious pest of cereal crops worldwide, and is highly sensitive to light signals during its developmental and reproductive stages. However, molecular biological studies of its response to light stress are scarce, and related genomic information is not available. In this study, we sequenced and de novo assembled the transcriptomes of M. separata exposed to four different light conditions: dark, white light (WL), UV light (UVL) and yellow light (YL). A total of 46,327 unigenes with an average size of 571 base pairs (bp) were obtained, among which 24,344 (52.55%) matched to public databases. The numbers of genes differentially expressed between dark vs WL, dark vs UVL, dark vs YL, and UVL vs YL were 12,012, 12,950, 14,855, and 13,504, respectively. These results suggest that light exposure altered gene expression patterns in M. separata. Putative genes involved in phototransduction-fly, phototransduction, circadian rhythm-fly, olfactory transduction, and taste transduction were identified. This study thus identified a series of candidate genes and pathways potentially related to light stress in M. separata. PMID:28345615

  3. Attenuation of maternal psychophysiological stress responses and the maternal cortisol awakening response over the course of human pregnancy.

    PubMed

    Entringer, Sonja; Buss, Claudia; Shirtcliff, Elizabeth A; Cammack, Alison L; Yim, Ilona S; Chicz-DeMet, Aleksandra; Sandman, Curt A; Wadhwa, Pathik D

    2010-05-01

    The effects of maternal stress during pregnancy may depend, in part, on the timing in gestation of the occurrence of stress. The aim of the present study was to examine the effect of stage of gestation on maternal psychophysiological responses to stress using a standardized laboratory paradigm and on the cortisol response to awakening (CAR). A longitudinal design was employed to quantify maternal psychophysiological stress reactivity [changes in heart rate (HR), blood pressure, salivary cortisol, and psychological distress in response to the trier social stress test (TSST)] and the CAR at approximately 17 and 31 weeks gestation in a sample of 148 women. To account for the possible effects of habituation when being exposed to the same stress protocol twice, a non-pregnant comparison group (CG, N = 36) also underwent these assessments at two time points, with a comparable time interval between the assessments. In both groups, the TSST elicited significant changes in maternal HR, mean arterial pressure, and psychological distress levels but not a significant increase in cortisol levels. Among the pregnant women (pregnant group(PG)), the stressor-induced increases in HR, blood pressure, and psychological distress were significantly lower at the second (31 weeks gestation) compared to the first (17 weeks gestation) assessment of pregnancy (all p < 0.01). The maternal CAR was also significantly attenuated in later compared to earlier gestation (p = 0.003). In the CG, there were no significant differences in psychophysiological stress responses and in the CAR across the two assessments. Among pregnant women there is a progressive attenuation of psychophysiological stress responses with advancing gestation. This attenuation is unlikely to be attributable to habituation. Individual differences in the degree of attenuation of stress responses over gestation may represent a novel marker of stress susceptibility in human pregnancy.

  4. Sexual Dimorphism in the Response of Mercurialis annua to Stress

    PubMed Central

    Orlofsky, Ezra M.; Kozhoridze, Giorgi; Lyubenova, Lyudmila; Ostrozhenkova, Elena; Winkler, J. Barbro; Schröder, Peter; Bacher, Adelbert; Eisenreich, Wolfgang; Guy, Micha; Golan-Goldhirsh, Avi

    2016-01-01

    The research presented stemmed from the observations that female plants of the annual dioecious Mercurialis annua outlive male plants. This led to the hypothesis that female plants of M. annua would be more tolerant to stress than male plants. This hypothesis was addressed in a comprehensive way, by comparing morphological, biochemical and metabolomics changes in female and male plants during their development and under salinity. There were practically no differences between the genders in vegetative development and physiological parameters. However, under salinity conditions, female plants produced significantly more new reproductive nodes. Gender-linked differences in peroxidase (POD) and glutathione transferases (GSTs) were involved in anti-oxidation, detoxification and developmental processes in M. annua. 1H NMR metabolite profiling of female and male M. annua plants showed that under salinity the activity of the TCA cycle increased. There was also an increase in betaine in both genders, which may be explainable by its osmo-compatible function under salinity. The concentration of ten metabolites changed in both genders, while ‘Female-only-response’ to salinity was detected for five metabolites. In conclusion, dimorphic responses of M. annua plant genders to stress may be attributed to female plants’ capacity to survive and complete the reproductive life cycle. PMID:27128954

  5. Autophagy as a Stress Response Pathway in the Immune System.

    PubMed

    Bhattacharya, Abhisek; Eissa, N Tony

    2015-01-01

    Macroautophagy, hereafter, referred to as autophagy, has long been regarded as a housekeeping pathway involved in intracellular degradation and energy recycling. These housekeeping and homeostatic functions are especially important during cellular stress, such as periods of nutrient deprivation. However, importance of autophagy extends far beyond its degradative functions. Recent evidence shows that autophagy plays an essential role in development, organization and functions of the immune system, and defects in autophagy lead to several diseases, including cancer and autoimmunity. In the immune system, autophagy is important in regulation of the innate and adaptive immune responses. This review focuses on the roles of autophagy in the adaptive immune system. We first introduce the autophagy pathway and provide a brief description of the major molecular players involved in autophagy. We then discuss the importance of autophagy as a stress integrator mechanism and provide relevant examples of this role of autophagy in adaptive immune cells. Then we proceed to describe how autophagy regulates development, activation and functions of different adaptive immune cells. In these contexts, we mention both degradative and non-degradative roles of autophagy, and illustrate their importance. We also discuss role of autophagy in antigen presenting cells, which play critical roles in the activation of adaptive immune cells. Further, we describe how autophagy regulates functions of different adaptive immune cells during infection, inflammation and autoimmunity.

  6. Transcriptome Responses to Combinations of Stresses in Arabidopsis1[W][OA

    PubMed Central

    Rasmussen, Simon; Barah, Pankaj; Suarez-Rodriguez, Maria Cristina; Bressendorff, Simon; Friis, Pia; Costantino, Paolo; Bones, Atle M.; Nielsen, Henrik Bjørn; Mundy, John

    2013-01-01

    Biotic and abiotic stresses limit agricultural yields, and plants are often simultaneously exposed to multiple stresses. Combinations of stresses such as heat and drought or cold and high light intensity have profound effects on crop performance and yields. Thus, delineation of the regulatory networks and metabolic pathways responding to single and multiple concurrent stresses is required for breeding and engineering crop stress tolerance. Many studies have described transcriptome changes in response to single stresses. However, exposure of plants to a combination of stress factors may require agonistic or antagonistic responses or responses potentially unrelated to responses to the corresponding single stresses. To analyze such responses, we initially compared transcriptome changes in 10 Arabidopsis (Arabidopsis thaliana) ecotypes using cold, heat, high-light, salt, and flagellin treatments as single stress factors as well as their double combinations. This revealed that some 61% of the transcriptome changes in response to double stresses were not predic from the responses to single stress treatments. It also showed that plants prioritized between potentially antagonistic responses for only 5% to 10% of the responding transcripts. This indicates that plants have evolved to cope with combinations of stresses and, therefore, may be bred to endure them. In addition, using a subset of this data from the Columbia and Landsberg erecta ecotypes, we have delineated coexpression network modules responding to single and combined stresses. PMID:23447525

  7. Plastid Osmotic Stress Activates Cellular Stress Responses in Arabidopsis1[C][W][OPEN

    PubMed Central

    Wilson, Margaret E.; Basu, Meera R.; Bhaskara, Govinal Badiger; Verslues, Paul E.; Haswell, Elizabeth S.

    2014-01-01

    Little is known about cytoplasmic osmoregulatory mechanisms in plants, and even less is understood about how the osmotic properties of the cytoplasm and organelles are coordinately regulated. We have previously shown that Arabidopsis (Arabidopsis thaliana) plants lacking functional versions of the plastid-localized mechanosensitive ion channels Mechanosensitive Channel of Small Conductance-Like2 (MSL2) and MSL3 contain leaf epidermal plastids under hypoosmotic stress, even during normal growth and development. Here, we use the msl2 msl3 mutant as a model to investigate the cellular response to constitutive plastid osmotic stress. Under unstressed conditions, msl2 msl3 seedlings exhibited several hallmarks of drought or environmental osmotic stress, including solute accumulation, elevated levels of the compatible osmolyte proline (Pro), and accumulation of the stress hormone abscisic acid (ABA). Furthermore, msl2 msl3 mutants expressed Pro and ABA metabolism genes in a pattern normally seen under drought or osmotic stress. Pro accumulation in the msl2 msl3 mutant was suppressed by conditions that reduce plastid osmotic stress or inhibition of ABA biosynthesis. Finally, treatment of unstressed msl2 msl3 plants with exogenous ABA elicited a much greater Pro accumulation response than in the wild type, similar to that observed in plants under drought or osmotic stress. These results suggest that osmotic imbalance across the plastid envelope can elicit a response similar to that elicited by osmotic imbalance across the plasma membrane and provide evidence for the integration of the osmotic state of an organelle into that of the cell in which it resides. PMID:24676856

  8. Cardioprotective stress response in the human fetal heart

    PubMed Central

    Coles, John G.; Boscarino, Cathy; Takahashi, Mark; Grant, Diane; Chang, Astra; Ritter, Julia; Dai, Xiaojing; Du, Changqing; Musso, Gabriel; Yamabi, Hideaki; Goncalves, Jason; Kumar, Ashu Sunny; Woodgett, James; Lu, Huanzhang; Hannigan, Gregory

    2016-01-01

    Objective We propose that the fetal heart is highly resilient to hypoxic stress. Our objective was to elucidate the human fetal gene expression profile in response to simulated ischemia and reperfusion to identify molecular targets that account for the innate cardioprotection exhibited by the fetal phenotype. Methods Primary cultures of human fetal cardiac myocytes (gestational age, 15–20 weeks) were exposed to simulated ischemia and reperfusion in vitro by using a simulated ischemic buffer under anoxic conditions. Total RNA from treated and baseline cells were isolated, reverse transcribed, and labeled with Cy3 or Cy5 and hybridized to a human cDNA microarray for expression analysis. This analysis revealed a highly significant (false discovery rate, <3%) suppression of interleukin 6 transcript levels during the reperfusion phase confirmed by means of quantitative polymerase chain reaction (0.25 ± 0.11-fold). Interleukin 6 signaling during ischemia and reperfusion was assessed at the protein expression level by means of Western measurements of interleukin 6 receptor, the signaling subunit of the interleukin 6 receptor complex (gp130), and signal transducer of activated transcription 3. Posttranslational changes in the protein kinase B signaling pathway were determined on the basis of the phosphorylation status of protein kinase B, mitogen-activated protein kinase, and glycogen synthase kinase 3β. The effect of suppression of a prohypertrophic kinase, integrin-linked kinase, with short-interfering RNA was determined in an ischemia and reperfusion–stressed neonatal rat cardiac myocyte model. Endogenous secretion of interleukin 6 protein in culture supernatants was measured by enzyme-linked immunosorbent assay. Results Human fetal cardiac myocytes exhibited a significantly lower rate of apoptosis induction during ischemia and reperfusion and after exposure to staurosporine and recombinant interleukin 6 compared with that observed in neonatal rat cardiac myocytes

  9. Intracellular proteins produced by mammalian cells in response to environmental stress

    NASA Technical Reports Server (NTRS)

    Goochee, Charles F.; Passini, Cheryl A.

    1988-01-01

    The nature of the response of mammalian cells to environmental stress is examined by reviewing results of studies where cultured mouse L cells and baby hamster kidney cells were exposed to heat shock and the synthesis of heat-shock proteins and stress-response proteins (including HSP70, HSC70, HSP90, ubiquitin, and GRP70) in stressed and unstressed cells was evaluated using 2D-PAGE. The intracellular roles of the individual stress response proteins are discussed together with the regulation of the stress response system.

  10. Stress Effects on Mood, HPA Axis, and Autonomic Response: Comparison of Three Psychosocial Stress Paradigms

    PubMed Central

    Giles, Grace E.; Mahoney, Caroline R.; Brunyé, Tad T.; Taylor, Holly A.; Kanarek, Robin B.

    2014-01-01

    Extensive experimental psychology research has attempted to parse the complex relationship between psychosocial stress, mood, cognitive performance, and physiological changes. To do so, it is necessary to have effective, validated methods to experimentally induce psychosocial stress. The Trier Social Stress Test (TSST) is the most commonly used method of experimentally inducing psychosocial stress, but it is resource intensive. Less resource intense psychosocial stress tasks include the Socially Evaluative Cold Pressor Task (SECPT) and a computerized mental arithmetic task (MAT). These tasks effectively produce a physiological and psychological stress response and have the benefits of requiring fewer experimenters and affording data collection from multiple participants simultaneously. The objective of this study was to compare the magnitude and duration of these three experimental psychosocial stress induction paradigms. On each of four separate days, participants completed either a control non-stressful task or one of the three experimental stressors: the TSST, SECPT, or MAT. We measured mood, working memory performance, salivary cortisol and alpha-amylase (AA), and heart rate. The TSST and SECPT exerted the most robust effects on mood and physiological measures. TSST effects were generally evident immediately post-stress as well as 10- and 20-minutes after stress cessation, whereas SECPT effects were generally limited to the duration of the stressor. The stress duration is a key determinant when planning a study that utilizes an experimental stressor, as researchers may be interested in collecting dependent measures prior to stress cessation. In this way, the TSST would allow the investigator a longer window to administer tasks of interest. PMID:25502466

  11. Transactional associations between youths' responses to peer stress and depression: the moderating roles of sex and stress exposure.

    PubMed

    Agoston, Anna M; Rudolph, Karen D

    2011-02-01

    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.

  12. Epigenetic programming of the stress response in male and female rats by prenatal restraint stress.

    PubMed

    Darnaudéry, Muriel; Maccari, Stefania

    2008-03-01

    Exposure to hostile conditions results in a series of coordinated responses aimed at enhancing the probability of survival. The activation of the hypothalamo-pituitary-adrenocortical (HPA) axis plays a pivotal role in the stress response. While the short-term activation of the HPA axis allows adaptive responses to the challenge, in the long run this can be devastating for the organism. In particular, life events occurring during the perinatal period have strong long-term effects on the behavioral and neuroendocrine response to stressors. In male and female rats exposed to prenatal restraint stress (PRS), these effects include a long-lasting hyperactivation of the HPA response associated with an altered circadian rhythm of corticosterone secretion. Furthermore, male animals exhibit sleep disturbances. In males, these HPA dysfunctions have been reported in infant, young, adult and aged animals, thus suggesting a permanent effect of early stress. Interestingly, after exposure to an intense inescapable footshock, female PRS rats durably exhibit a blunted corticosterone secretion response to stress. In male PRS rats exposed to an alcohol challenge, the HPA axis is similarly hyporesponsive. Rats exposed to PRS also show behavioral disturbances. Both male and female PRS rats show high anxiety levels and depression-like behavior during adulthood, although some studies suggest that female PRS rats present low anxiety levels. With ageing, male and female PRS rats exhibit memory impairments in hippocampus-dependent tasks, while female PRS rats improve their memory performance during adulthood. The gender effect on behavior seems to be related to a reduction in hippocampal plasticity in male PRS rats, and an increase in female PRS rats. Despite the permanent imprinting induced by early stress, the dysfunctions observed after PRS can be reversed by environmental or pharmacological strategies such as environmental enrichment or antidepressive and neurotrophic treatments

  13. Infants, Mothers, and Dyadic Contributions to Stability and Prediction of Social Stress Response at 6 Months

    ERIC Educational Resources Information Center

    Provenzi, Livio; Olson, Karen L.; Montirosso, Rosario; Tronick, Ed

    2016-01-01

    The study of infants' interactive style and social stress response to repeated stress exposures is of great interest for developmental and clinical psychologists. Stable maternal and dyadic behavior is critical to sustain infants' development of an adaptive social stress response, but the association between infants' interactive style and social…

  14. Evolution and Ontogeny of Stress Response to Social Challenges in the Human Child

    ERIC Educational Resources Information Center

    Flinn, Mark V.

    2006-01-01

    The stress response systems of the human child are highly sensitive to social challenges. Because stress hormones can have negative developmental and health consequences, this presents an evolutionary paradox: Why would natural selection have favored mechanisms that elevate stress hormone levels in response to psychosocial stimuli? Two…

  15. Group VII Ethylene Response Factors Coordinate Oxygen and Nitric Oxide Signal Transduction and Stress Responses in Plants.

    PubMed

    Gibbs, Daniel J; Conde, Jorge Vicente; Berckhan, Sophie; Prasad, Geeta; Mendiondo, Guillermina M; Holdsworth, Michael J

    2015-09-01

    The group VII ethylene response factors (ERFVIIs) are plant-specific transcription factors that have emerged as important regulators of abiotic and biotic stress responses, in particular, low-oxygen stress. A defining feature of ERFVIIs is their conserved N-terminal domain, which renders them oxygen- and nitric oxide (NO)-dependent substrates of the N-end rule pathway of targeted proteolysis. In the presence of these gases, ERFVIIs are destabilized, whereas an absence of either permits their accumulation; ERFVIIs therefore coordinate plant homeostatic responses to oxygen availability and control a wide range of NO-mediated processes. ERFVIIs have a variety of context-specific protein and gene interaction partners, and also modulate gibberellin and abscisic acid signaling to regulate diverse developmental processes and stress responses. This update discusses recent advances in our understanding of ERFVII regulation and function, highlighting their role as central regulators of gaseous signal transduction at the interface of ethylene, oxygen, and NO signaling.

  16. 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

  17. Stress responsive DEAD-box helicases: a new pathway to engineer plant stress tolerance.

    PubMed

    Vashisht, Ajay Amar; Tuteja, Narendra

    2006-08-01

    Abiotic stresses including various environmental factors adversely affect plant growth and limit agricultural production worldwide. Minimizing these losses is a major area of concern for all countries. Therefore, it is desirable to develop multi-stress tolerant varieties. Salinity, drought, and cold are among the major environmental stresses that greatly influence the growth, development, survival, and yield of plants. UV-B radiation of sunlight, which damages the cellular genomes, is another growth-retarding factor. Several genes are induced under the influence of various abiotic stresses. Among these are DNA repair genes, which are induced in response to the DNA damage. Since the stresses affect the cellular gene expression machinery, it is possible that molecules involved in nucleic acid metabolism including helicases are likely to be affected. The light-driven shifts in redox-potential can also initiate the helicase gene expression. Helicases are ubiquitous enzymes that catalyse the unwinding of energetically stable duplex DNA (DNA helicases) or duplex RNA secondary structures (RNA helicases). Most helicases are members of DEAD-box protein superfamily and play essential roles in basic cellular processes such as DNA replication, repair, recombination, transcription, ribosome biogenesis and translation initiation. Therefore, helicases might be playing an important role in regulating plant growth and development under stress conditions by regulating some stress-induced pathways. There are now few reports on the up-regulation of DEAD-box helicases in response to abiotic stresses. Recently, salinity-stress tolerant tobacco plants have already been raised by overexpressing a helicase gene, which suggests a new pathway to engineer plant stress tolerance [N. Sanan-Mishra, X.H. Pham, S.K. Sopory, N. Tuteja, Pea DNA helicase 45 overexpression in tobacco confers high salinity tolerance without affecting yield. Proc. Natl. Acad. Sci. USA 102 (2005) 509-514]. Presently the

  18. Coordination of cortisol response to social evaluative threat with autonomic and inflammatory responses is moderated by stress appraisals and affect.

    PubMed

    Laurent, Heidemarie K; Lucas, Todd; Pierce, Jennifer; Goetz, Stefan; Granger, Douglas A

    2016-07-01

    Recent approaches to stress regulation have emphasized coordination among multiple biological systems. This study builds on evidence that hypothalamic-pituitary-adrenal (HPA) axis activity should be considered in coordination with other stress-sensitive biological systems to characterize healthy responses. Healthy African-Americans (n=115) completed the Trier Social Stress Test, and biological responses were assessed through salivary cortisol, dehydroepiandrosterone-sulfate (DHEA-S), alpha amylase (sAA), and C-reactive protein (sCRP). Multilevel modeling demonstrated that cortisol responses typically aligned with changes in DHEA-S, sAA, and sCRP across the session. At the same time, the degree of cortisol coordination with sAA and sCRP varied by participants' subjective stress following the task; participants with higher secondary stress appraisals showed greater cortisol-sAA alignment, whereas those experiencing more negative affect showed greater cortisol-sCRP alignment. Results highlight the importance of a multisystem approach to stress and suggest that positive HPA axis coordination with the autonomic response, but not with the immune/inflammatory response, may be adaptive.

  19. Acute stress responses: A review and synthesis of ASD, ASR, and CSR.

    PubMed

    Isserlin, Leanna; Zerach, Gadi; Solomon, Zahava

    2008-10-01

    Toward the development of a unifying diagnosis for acute stress responses this article attempts to find a place for combat stress reaction (CSR) within the spectrum of other defined acute stress responses. This article critically compares the diagnostic criteria of acute stress disorder (ASD), acute stress reaction (ASR), and CSR. Prospective studies concerning the predictive value of ASD, ASR, and CSR are reviewed. Questions, recommendations, and implications for clinical practice are raised concerning the completeness of the current acute stress response diagnoses, the heterogeneity of different stressors, the scope of expected outcomes, and the importance of decline in function as an indicator of future psychological, psychiatric, and somatic distress.

  20. 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.

  1. p53-dependent ceramide response to genotoxic stress.

    PubMed Central

    Dbaibo, G S; Pushkareva, M Y; Rachid, R A; Alter, N; Smyth, M J; Obeid, L M; Hannun, Y A

    1998-01-01

    Both p53 and ceramide have been implicated in the regulation of growth suppression. p53 has been proposed as the "guardian of the genome" and ceramide has been suggested as a "tumor suppressor lipid. " Both molecules appear to regulate cell cycle arrest, senescence, and apoptosis. In this study, we investigated the relationship between p53 and ceramide. We found that treatment of Molt-4 cells with low concentrations of actinomycin D or gamma-irradiation, which activate p53-dependent apoptosis, induces apoptosis only in cells expressing normal levels of p53. In these cells, p53 activation was followed by a dose- and time-dependent increase in endogenous ceramide levels which was not seen in cells lacking functional p53 and treated similarly. Similar results were seen in irradiated L929 cells whereby the p53-deficient clone was significantly more resistant to irradiation and exhibited no ceramide response. However, in p53-independent systems, such as growth suppression induced by TNF-alpha or serum deprivation, ceramide accumulated irrespective of the upregulation of p53, indicating that p53 regulates ceramide accumulation in only a subset of growth-suppressive pathways. Finally, ceramide did not increase p53 levels when used at growth-suppressive concentrations. Also, when cells lacking functional p53, either due to mutation or the expression of the E6 protein of human papilloma virus, were treated with exogenous ceramide, there was equal growth suppression, cell cycle arrest, and apoptosis as compared with cells expressing normal p53. These results indicate that p53 is unlikely to function "downstream" of ceramide. Instead, they suggest that, in situations where p53 performs a critical regulatory role, such as the response to genotoxic stress, it functions "upstream" of ceramide. These studies begin to define a relationship between these two pathways of growth inhibition. PMID:9664074

  2. Cellular Response of Shewanella oneidensis to StrontiumStress

    SciTech Connect

    Brown, Steven D.; Martin, Madhavi; Deshpande, Sameer; Seal,Sudipta; Huang, Katherine; Alm, Eric; Yang, Yunfeng; Wu, Liyou; Yan,Tengfen; Liu, Xueduan; Arkin, Adam; Chourey, Karuna; Zhou, Jizhong; Thompson, Dorothea K.

    2007-03-30

    The physiology and transcriptome dynamics of the metalion-reducing bacterium Shewanella oneidensis strain MR-1 in response tononradioactive strontium (Sr) exposure were investigated. Studiesindicated that MR-1 was able to grow aerobically in complex medium in thepresence of 180 mMSrCl2 but showed severe growth inhibition at levelsabove that concentration. Temporal gene expression profiles weregenerated from aerobically grown, mid-exponential-phase MR-1 cellsshocked with 180 mM SrCl2 and analyzed for significant differences inmRNA abundance with reference to data for nonstressed MR-1 cells. Geneswith annotated functions in siderophore biosynthesis and iron transportwere among the most highly induced (>100-fold [P<0.05]) openreading frames in response to acute Sr stress, and a mutant(SO3032::pKNOCK) defective in siderophore production was found to behypersensitive to SrCl2 exposure, compared to parental and wild-typestrains. Transcripts encoding multidrug and heavy metal efflux pumps,proteins involved in osmotic adaptation, sulfate ABC transporters, andassimilative sulfur metabolism enzymes also were differentially expressedfollowing Sr exposure but at levels that were several orders of magnitudelower than those for iron transport genes. Precipitate formation wasobserved during aerobic growth of MR-1 in broth cultures amended with 50,100, or 150 mM SrCl2 but not in cultures of the SO3032::pKNOCK mutant orin the abiotic control. Chemical analysis of this precipitate usinglaser-induced breakdown spectroscopy and static secondary ion massspectrometry indicated extracellular solid-phase sequestration of Sr,with at least a portion of the heavy metal associated with carbonatephases.

  3. Stress response: anything that doesn't kill you makes you stronger.

    PubMed

    Gartner, Anton; Akay, Alper

    2013-11-18

    A new study shows that DNA damage not only elicits response pathways directly related to DNA repair but also induces a response that extensively overlaps with the pathogen infection pathway and confers resistance to both oxidative stress and heat shock.

  4. Ethylene Response Factors: A Key Regulatory Hub in Hormone and Stress Signaling.

    PubMed

    Müller, Maren; Munné-Bosch, Sergi

    2015-09-01

    Ethylene is essential for many developmental processes and a key mediator of biotic and abiotic stress responses in plants. The ethylene signaling and response pathway includes Ethylene Response Factors (ERFs), which belong to the transcription factor family APETALA2/ERF. It is well known that ERFs regulate molecular response to pathogen attack by binding to sequences containing AGCCGCC motifs (the GCC box), a cis-acting element. However, recent studies suggest that several ERFs also bind to dehydration-responsive elements and act as a key regulatory hub in plant responses to abiotic stresses. Here, we review some of the recent advances in our understanding of the ethylene signaling and response pathway, with emphasis on ERFs and their role in hormone cross talk and redox signaling under abiotic stresses. We conclude that ERFs act as a key regulatory hub, integrating ethylene, abscisic acid, jasmonate, and redox signaling in the plant response to a number of abiotic stresses.

  5. Ethylene Response Factors: A Key Regulatory Hub in Hormone and Stress Signaling1

    PubMed Central

    Müller, Maren; Munné-Bosch, Sergi

    2015-01-01

    Ethylene is essential for many developmental processes and a key mediator of biotic and abiotic stress responses in plants. The ethylene signaling and response pathway includes Ethylene Response Factors (ERFs), which belong to the transcription factor family APETALA2/ERF. It is well known that ERFs regulate molecular response to pathogen attack by binding to sequences containing AGCCGCC motifs (the GCC box), a cis-acting element. However, recent studies suggest that several ERFs also bind to dehydration-responsive elements and act as a key regulatory hub in plant responses to abiotic stresses. Here, we review some of the recent advances in our understanding of the ethylene signaling and response pathway, with emphasis on ERFs and their role in hormone cross talk and redox signaling under abiotic stresses. We conclude that ERFs act as a key regulatory hub, integrating ethylene, abscisic acid, jasmonate, and redox signaling in the plant response to a number of abiotic stresses. PMID:26103991

  6. Attentional orienting toward social stress stimuli predicts increased cortisol responsivity to psychosocial stress irrespective of the early socioeconomic status.

    PubMed

    Pilgrim, Kamala; Marin, Marie-France; Lupien, Sonia J

    2010-05-01

    The principal aim of the study was to examine how the natural tendency to shift attention toward or away from social stress stimuli during a restful state, relates to the magnitude of cortisol elicited in response to a stressful context. It also assessed whether any relationship that did emerge between attentional biases and cortisol responsivity would be associated with the childhood socioeconomic status (SES). Twenty-five healthy normal controls rested for 45min during which time they completed an adaptation of Posner's attentional orienting paradigm comprising social stress words as cues. Immediately following, participants were exposed to a public stressful speech task adapted from the Trier Social Stress Test (TSST). Results indicated that a rapid attentional engagement in the direction of social stress words prior to stress exposure related to a pronounced cortisol response to the stress task, while a slow attentional engagement toward social stress words was related to a weak cortisol response to the stress task. It was also found that fast engagers of social stress information displayed lower self-esteem than slow engagers. Groups did not differ in terms of their reported past SES. These findings demonstrate that attentional biases for social stress stimuli at rest predict the magnitude of cortisol likely to be elicited in response to a subsequent stressor. A natural tendency to rapidly shift attention toward social stress-related information may be the driving force behind cortisol reactivity when handling psychological forms of stress, independent of the early SES environment.

  7. Repeated forced swim stress differentially affects formalin-evoked nociceptive behaviour and the endocannabinoid system in stress normo-responsive and stress hyper-responsive rat strains.

    PubMed

    Jennings, Elaine M; Okine, Bright N; Olango, Weredeselam M; Roche, Michelle; Finn, David P

    2016-01-04

    Repeated exposure to a homotypic stressor such as forced swimming enhances nociceptive responding in rats. However, the influence of genetic background on this stress-induced hyperalgesia is poorly understood. The aim of the present study was to compare the effects of repeated forced swim stress on nociceptive responding in Sprague-Dawley (SD) rats versus the Wistar Kyoto (WKY) rat strain, a genetic background that is susceptible to stress, negative affect and hyperalgesia. Given the well-documented role of the endocannabinoid system in stress and pain, we investigated associated alterations in endocannabinoid signalling in the dorsal horn of the spinal cord and amygdala. In SD rats, repeated forced swim stress for 10 days was associated with enhanced late phase formalin-evoked nociceptive behaviour, compared with naive, non-stressed SD controls. In contrast, WKY rats exposed to 10 days of swim stress displayed reduced late phase formalin-evoked nociceptive behaviour. Swim stress increased levels of monoacylglycerol lipase (MAGL) mRNA in the ipsilateral side of the dorsal spinal cord of SD rats, an effect not observed in WKY rats. In the amygdala, swim stress reduced anandamide (AEA) levels in the contralateral amygdala of SD rats, but not WKY rats. Additional within-strain differences in levels of CB1 receptor and fatty acid amide hydrolase (FAAH) mRNA and levels of 2-arachidonylglycerol (2-AG) were observed between the ipsilateral and contralateral sides of the dorsal horn and/or amygdala. These data indicate that the effects of repeated stress on inflammatory pain-related behaviour are different in two rat strains that differ with respect to stress responsivity and affective state and implicate the endocannabinoid system in the spinal cord and amygdala in these differences.

  8. Gender-Related Differences in Cardiovascular Responses to Orthostatic Stress

    NASA Technical Reports Server (NTRS)

    Fritsch-Yelle, Janice M.; DAunno, Dominick S.; Waters, Wendy W.; Freeman-Perez, Sondra

    1999-01-01

    There is evidence that men and women have different cardiovascular responses to standing, and that women are more susceptible to orthostatic hypotension than men. The present study seeks to determine if decreased orthostatic tolerance in women is caused by diminished vasoconstrictive responses.

  9. The Stress Response Systems: Universality and Adaptive Individual Differences

    ERIC Educational Resources Information Center

    Ellis, Bruce J.; Jackson, Jenee James; Boyce, W. Thomas

    2006-01-01

    Biological reactivity to psychological stressors comprises a complex, integrated system of central neural and peripheral neuroendocrine responses designed to prepare the organism for challenge or threat. Developmental experience plays a role, along with heritable variation, in calibrating the response dynamics of this system. This calibration…

  10. 2010 MICROBIAL STRESS RESPONSE GORDON RESEARCH CONFERENCE, JULY 18-23, 2010

    SciTech Connect

    Sarah Ades

    2011-07-23

    The 2010 Gordon Research Conference on Microbial Stress Responses provides an open and exciting forum for the exchange of scientific discoveries on the remarkable mechanisms used by microbes to survive in nearly every niche on the planet. Understanding these stress responses is critical for our ability to control microbial survival, whether in the context of biotechnology, ecology, or pathogenesis. From its inception in 1994, this conference has traditionally employed a very broad definition of stress in microbial systems. Sessions will cover the major steps of stress responses from signal sensing to transcriptional regulation to the effectors that mediate responses. A wide range of stresses will be represented. Some examples include (but are not limited to) oxidative stress, protein quality control, antibiotic-induced stress and survival, envelope stress, DNA damage, and nutritional stress. The 2010 meeting will also focus on the role of stress responses in microbial communities, applied and environmental microbiology, and microbial development. This conference brings together researchers from both the biological and physical sciences investigating stress responses in medically- and environmentally relevant microbes, as well as model organisms, using cutting-edge techniques. Computational, systems-level, and biophysical approaches to exploring stress responsive circuits will be integrated throughout the sessions alongside the more traditional molecular, physiological, and genetic approaches. The broad range of excellent speakers and topics, together with the intimate and pleasant setting at Mount Holyoke College, provide a fertile ground for the exchange of new ideas and approaches.

  11. The response of the yeast Saccharomyces cerevisiae to sudden vs. gradual changes in environmental stress monitored by expression of the stress response protein Hsp12p.

    PubMed

    Nisamedtinov, Ildar; Lindsey, George G; Karreman, Robert; Orumets, Kerti; Koplimaa, Mariane; Kevvai, Kaspar; Paalme, Toomas

    2008-09-01

    The response of the yeast Saccharomyces cerevisiae to sudden vs. gradual changes in different environmental stress conditions during both respiratory growth and aerobic fermentative growth in the presence of excess glucose was investigated by monitoring the level and rate of expression of the stress response protein Hsp12p using the fluorescent fusion construct Hsp12p-Gfp2p. The initial expression level and the rate of Hsp12p synthesis was significantly greater under glucose-limited conditions in the chemostat (D<0.14 h(-1)) compared with when excess glucose was present in the auxostat. Decreasing the dilution rate and the glucose concentration further in the A-stat resulted in increased Hsp12p expression, which was more marked when a rapid rather than a gradual change was affected. Common stress factors such as NaCl, ethanol and elevated temperature caused stress responses in both D-stat and auxo-accelerostat culture. The magnitude of the stress response depended on the stress factor, cultivation conditions as well as the rate of change of the stress factor. The rate of Hsp12p synthesis increased due to all applied stresses, with the observed increase between 2 and 20 times lower when the stress was applied gradually rather than rapidly. The results suggested that the Hsp12p expression rate is a good indicator of applied stress in S. cerevisiae.

  12. Triggers of the HSP70 stress response: environmental responses and laboratory manipulation in an Antarctic marine invertebrate (Nacella concinna).

    PubMed

    Clark, Melody S; Peck, Lloyd S

    2009-11-01

    The Antarctic limpet, Nacella concinna, exhibits the classical heat shock response, with up-regulation of duplicated forms of the inducible heat shock protein 70 (HSP70) gene in response to experimental manipulation of seawater temperatures. However, this response only occurs in the laboratory at temperatures well in excess of any experienced in the field. Subsequent environmental sampling of inter-tidal animals also showed up-regulation of these genes, but at temperature thresholds much lower than those required to elicit a response in the laboratory. It was hypothesised that this was a reflection of the complexity of the stresses encountered in the inter-tidal region. Here, we describe a further series of experiments comprising both laboratory manipulation and environmental sampling of N. concinna. We investigate the expression of HSP70 gene family members (HSP70A, HSP70B, GRP78 and HSC70) in response to a further suite of environmental stressors: seasonal and experimental cold, freshwater, desiccation, chronic heat and periodic emersion. Lowered temperatures (-1.9 degrees C and -1.6 degrees C), generally produced a down-regulation of all HSP70 family members, with some up-regulation of HSC70 when emerging from the winter period and increasing sea temperatures. There was no significant response to freshwater immersion. In response to acute and chronic heat treatments plus simulated tidal cycles, the data showed a clear pattern. HSP70A showed a strong but very short-term response to heat whilst the duplicated HSP70B also showed heat to be a trigger, but had a more sustained response to complex stresses. GRP78 expression indicates that it was acting as a generalised stress response under the experimental conditions described here. HSC70 was the major chaperone invoked in response to long-term stresses of varying types. These results provide intriguing clues not only to the complexity of HSP70 gene expression in response to environmental change but also insights

  13. A huntingtin-mediated fast stress response halting endosomal trafficking is defective in Huntington's disease

    PubMed Central

    Nath, Siddharth; Munsie, Lise N.; Truant, Ray

    2015-01-01

    Cellular stress is a normal part of the aging process and is especially relevant in neurodegenerative disease. Canonical stress responses, such as the heat shock response, activate following exposure to stress and restore proteostasis through the action of isomerases and chaperones within the cytosol. Through live-cell imaging, we demonstrate involvement of the Huntington's disease (HD) protein, huntingtin, in a rapid cell stress response that lies temporally upstream of canonical stress responses. This response is characterized by the formation of distinct cytosolic puncta and reversible localization of huntingtin to early endosomes. The formation of these puncta, which we have termed huntingtin stress bodies (HSBs), is associated with arrest of early-to-recycling and early-to-late endosomal trafficking. The critical domains for this response have been mapped to two regions of huntingtin flanking the polyglutamine tract, and we observe polyglutamine-expanded huntingtin-expressing cells to be defective in their ability to recover from this stress response. We propose that HSB formation rapidly diverts high ATP use from vesicular trafficking during stress, thus mobilizing canonical stress responses without relying on increased energy metabolism, and that restoration from this response is defective in HD. PMID:25205111

  14. Acid and base stress and transcriptomic responses in Bacillus subtilis.

    PubMed

    Wilks, Jessica C; Kitko, Ryan D; Cleeton, Sarah H; Lee, Grace E; Ugwu, Chinagozi S; Jones, Brian D; BonDurant, Sandra S; Slonczewski, Joan L

    2009-02-01

    Acid and base environmental stress responses were investigated in Bacillus subtilis. B. subtilis AG174 cultures in buffered potassium-modified Luria broth were switched from pH 8.5 to pH 6.0 and recovered growth rapidly, whereas cultures switched from pH 6.0 to pH 8.5 showed a long lag time. Log-phase cultures at pH 6.0 survived 60 to 100% at pH 4.5, whereas cells grown at pH 7.0 survived <15%. Cells grown at pH 9.0 survived 40 to 100% at pH 10, whereas cells grown at pH 7.0 survived <5%. Thus, growth in a moderate acid or base induced adaptation to a more extreme acid or base, respectively. Expression indices from Affymetrix chip hybridization were obtained for 4,095 protein-encoding open reading frames of B. subtilis grown at external pH 6, pH 7, and pH 9. Growth at pH 6 upregulated acetoin production (alsDS), dehydrogenases (adhA, ald, fdhD, and gabD), and decarboxylases (psd and speA). Acid upregulated malate metabolism (maeN), metal export (czcDO and cadA), oxidative stress (catalase katA; OYE family namA), and the SigX extracytoplasmic stress regulon. Growth at pH 9 upregulated arginine catabolism (roc), which generates organic acids, glutamate synthase (gltAB), polyamine acetylation and transport (blt), the K(+)/H(+) antiporter (yhaTU), and cytochrome oxidoreductases (cyd, ctaACE, and qcrC). The SigH, SigL, and SigW regulons were upregulated at high pH. Overall, greater genetic adaptation was seen at pH 9 than at pH 6, which may explain the lag time required for growth shift to high pH. Low external pH favored dehydrogenases and decarboxylases that may consume acids and generate basic amines, whereas high external pH favored catabolism-generating acids.

  15. Biochemical and molecular responses to water stress in resurrection plants.

    PubMed

    Bernacchia, Giovanni; Furini, Antonella

    2004-06-01

    A small group of angiosperms, known as resurrection plants, can tolerate extreme dehydration. They survive in arid environments because they are able to dehydrate, remain quiescent during long periods of drought, and then resurrect upon rehydration. Dehydration induces the expression of a large number of transcripts in resurrection plants. Gene products with a putative protective function such as LEA proteins have been identified; they are expressed at high levels in the cytoplasm or in chloroplasts upon dehydration and/or ABA treatment of vegetative tissue. An increase in sugar concentration is usually observed at the onset of desiccation in vegetative tissue of resurrection plants. These sugars may be effective in osmotic adjustment or they may stabilize membrane structures and proteins. Regulatory genes such as a protein translation initiation factor, homeodomain-leucine zipper genes and a gene probably working as a regulatory RNA have been isolated and characterized. The knowledge of the biochemical and molecular responses that occur during the onset of drought may help to improve water stress tolerance in plants of agronomic importance.

  16. Stress responses of spring rape plants to soil flooding

    NASA Astrophysics Data System (ADS)

    Balakhnina, T.; Bennicelli, R.; Stêpniewska, Z.; Stêpniewski, W.; Borkowska, A.; Fomina, I.

    2012-10-01

    Stress responses of spring rape to soil hypoxia were investigated during 8-days flooding. Soil air-filled porosity decreased from 25-30% to 0%, oxygen diffusion rate - from 2.6-3.5 to 0.34 μmol O2 m-2 s-1, and redox potential - from 460 to 150mVwithin few hours. Alcohol dehydrogenase activity in roots increased up to 7-fold after one day of flooding and then decreased to 170% of control. Superoxide dismutase activity in roots increased by 27% during first 3 days and then dropped to 60% of control; in the leaves superoxide dismutase activity increased in average by 44%. Ascorbate peroxidase activity in leaves increased by 37% during first 3 days and then decreased to control value. Glutathione reductase activity increased by 45% in roots of flooded plants but did not change in leaves. Proline concentration in leaves increased up to 4-fold on the 3d day of flooding and then decreased to control value. Thus soil flooding induces increase of alcohol dehydrogenase activity and subsequent increase of superoxide dismutase and glutathione reductase activities in roots while the leaves display a few days increase of free proline concentration and ascorbate peroxidase activity, and a long-term increase of superoxide dismutase activity.

  17. Response of automated tow placed laminates to stress concentrations

    NASA Technical Reports Server (NTRS)

    Cairns, Douglas S.; Ilcewicz, Larry B.; Walker, Tom

    1993-01-01

    In this study, the response of laminates with stress concentrations is explored. Automated Tow Placed (ATP, also known as Fiber Placement) laminates are compared to conventional tape layup manufacturing. Previous tensile fracture tests on fiber placed laminates show an improvement in tensile fracture of large notches over 20 percent compared to tape layup laminates. A hierarchial modeling scheme is presented. In this scheme, a global model is developed for laminates with notches. A local model is developed to study the influence of inhomogeneities at the notch tip, which are a consequence of the fiber placement manufacturing technique. In addition, a stacked membrane model was developed to study delaminations and splitting on a ply-by-ply basis. The results indicate that some benefit with respect to tensile fracture (up to 11 percent) can be gained from inhomogeneity alone, but that the most improvement may be obtained with splitting and delaminations which are more severe in the case of fiber placement compared to tape layup. Improvements up to 36 percent were found from the model for fiber placed laminates with damage at the notch tip compared to conventional tape layup.

  18. Identification of genes involved in the response of Arabidopsis to simultaneous biotic and abiotic stresses.

    PubMed

    Atkinson, Nicky J; Lilley, Catherine J; Urwin, Peter E

    2013-08-01

    In field conditions, plants may experience numerous environmental stresses at any one time. Research suggests that the plant response to multiple stresses is different from that for individual stresses, producing nonadditive effects. In particular, the molecular signaling pathways controlling biotic and abiotic stress responses may interact and antagonize one another. The transcriptome response of Arabidopsis (Arabidopsis thaliana) to concurrent water deficit (abiotic stress) and infection with the plant-parasitic nematode Heterodera schachtii (biotic stress) was analyzed by microarray. A unique program of gene expression was activated in response to a combination of water deficit and nematode stress, with 50 specifically multiple-stress-regulated genes. Candidate genes with potential roles in controlling the response to multiple stresses were selected and functionally characterized. RAPID ALKALINIZATION FACTOR-LIKE8 (AtRALFL8) was induced in roots by joint stresses but conferred susceptibility to drought stress and nematode infection when overexpressed. Constitutively expressing plants had stunted root systems and extended root hairs. Plants may produce signal peptides such as AtRALFL8 to induce cell wall remodeling in response to multiple stresses. The methionine homeostasis gene METHIONINE GAMMA LYASE (AtMGL) was up-regulated by dual stress in leaves, conferring resistance to nematodes when overexpressed. It may regulate methionine metabolism under conditions of multiple stresses. AZELAIC ACID INDUCED1 (AZI1), involved in defense priming in systemic plant immunity, was down-regulated in leaves by joint stress and conferred drought susceptibility when overexpressed, potentially as part of abscisic acid-induced repression of pathogen response genes. The results highlight the complex nature of multiple stress responses and confirm the importance of studying plant stress factors in combination.

  19. The stressed host response to infection: the disruptive signals and rhythms of systemic inflammation.

    PubMed

    Lowry, Stephen F

    2009-04-01

    The cognate signals from sterile or pathogen-induced sources converge on the same recognition or response pathways. In the surgical patient, a systemic response to infection most often occurs in the context of ongoing inflammatory stress. Such an inflammatory response is modulated initially by the magnitude of injury and by patient-specific (endogenous) factors, such as confounding illness, age, and genetic variation. Over an extended period of stress, treatmentrelated (exogenous) factors add unpredictability to host responses to subsequent challenges, such as acquired infection. The host response is discussed in the context of how existing sterile stressors may modify the response to acquired infection in surgical patients.

  20. BAP1 inhibits the ER stress gene regulatory network and modulates metabolic stress response.

    PubMed

    Dai, Fangyan; Lee, Hyemin; Zhang, Yilei; Zhuang, Li; Yao, Hui; Xi, Yuanxin; Xiao, Zhen-Dong; You, M James; Li, Wei; Su, Xiaoping; Gan, Boyi

    2017-03-21

    The endoplasmic reticulum (ER) is classically linked to metabolic homeostasis via the activation of unfolded protein response (UPR), which is instructed by multiple transcriptional regulatory cascades. BRCA1 associated protein 1 (BAP1) is a tumor suppressor with de-ubiquitinating enzyme activity and has been implicated in chromatin regulation of gene expression. Here we show that BAP1 inhibits cell death induced by unresolved metabolic stress. This prosurvival role of BAP1 depends on its de-ubiquitinating activity and correlates with its ability to dampen the metabolic stress-induced UPR transcriptional network. BAP1 inhibits glucose deprivation-induced reactive oxygen species and ATP depletion, two cellular events contributing to the ER stress-induced cell death. In line with this, Bap1 KO mice are more sensitive to tunicamycin-induced renal damage. Mechanically, we show that BAP1 represses metabolic stress-induced UPR and cell death through activating transcription factor 3 (ATF3) and C/EBP homologous protein (CHOP), and reveal that BAP1 binds to ATF3 and CHOP promoters and inhibits their transcription. Taken together, our results establish a previously unappreciated role of BAP1 in modulating the cellular adaptability to metabolic stress and uncover a pivotal function of BAP1 in the regulation of the ER stress gene-regulatory network. Our study may also provide new conceptual framework for further understanding BAP1 function in cancer.

  1. BAP1 inhibits the ER stress gene regulatory network and modulates metabolic stress response

    PubMed Central

    Dai, Fangyan; Lee, Hyemin; Zhang, Yilei; Zhuang, Li; Yao, Hui; Xi, Yuanxin; Xiao, Zhen-Dong; You, M. James; Li, Wei; Su, Xiaoping; Gan, Boyi

    2017-01-01

    The endoplasmic reticulum (ER) is classically linked to metabolic homeostasis via the activation of unfolded protein response (UPR), which is instructed by multiple transcriptional regulatory cascades. BRCA1 associated protein 1 (BAP1) is a tumor suppressor with de-ubiquitinating enzyme activity and has been implicated in chromatin regulation of gene expression. Here we show that BAP1 inhibits cell death induced by unresolved metabolic stress. This prosurvival role of BAP1 depends on its de-ubiquitinating activity and correlates with its ability to dampen the metabolic stress-induced UPR transcriptional network. BAP1 inhibits glucose deprivation-induced reactive oxygen species and ATP depletion, two cellular events contributing to the ER stress-induced cell death. In line with this, Bap1 KO mice are more sensitive to tunicamycin-induced renal damage. Mechanically, we show that BAP1 represses metabolic stress-induced UPR and cell death through activating transcription factor 3 (ATF3) and C/EBP homologous protein (CHOP), and reveal that BAP1 binds to ATF3 and CHOP promoters and inhibits their transcription. Taken together, our results establish a previously unappreciated role of BAP1 in modulating the cellular adaptability to metabolic stress and uncover a pivotal function of BAP1 in the regulation of the ER stress gene-regulatory network. Our study may also provide new conceptual framework for further understanding BAP1 function in cancer. PMID:28275095

  2. Second-hand stress: inhalation of stress sweat enhances neural response to neutral faces

    PubMed Central

    Rubin, Denis; Botanov, Yevgeny; Hajcak, Greg

    2012-01-01

    This study investigated whether human chemosensory-stress cues affect neural activity related to the evaluation of emotional stimuli. Chemosensory stimuli were obtained from the sweat of 64 male donors during both stress (first-time skydive) and control (exercise) conditions, indistinguishable by odor. We then recorded event-related potentials (ERPs) from an unrelated group of 14 participants while they viewed faces morphed with neutral-to-angry expressions and inhaled nebulized stress and exercise sweat in counter-balanced blocks, blind to condition. Results for the control condition ERPs were consistent with previous findings: the late positive potential (LPP; 400–600 ms post stimulus) in response to faces was larger for threatening than both neutral and ambiguous faces. In contrast, the stress condition was associated with a heightened LPP across all facial expressions; relative to control, the LPP was increased for both ambiguous and neutral faces in the stress condition. These results suggest that stress sweat may impact electrocortical activity associated with attention to salient environmental cues, potentially increasing attentiveness to otherwise inconspicuous stimuli. PMID:21208988

  3. Role of various hormones in photosynthetic responses of green plants under environmental stresses.

    PubMed

    Poonam; Bhardwaj, Renu; Kaur, Ravdeep; Bali, Shagun; Kaur, Parminder; Sirhindi, Geetika; Thukral, Ashwani K; Ohri, Puja; Vig, Adarsh P

    2015-01-01

    Environmental stress includes adverse factors like water deficit, high salinity, enhanced temperature and heavy metals etc. These stresses alter the normal growth and metabolic processes of plants including photosynthesis. Major photosynthetic responses under various stresses include inhibition of photosystems (I and II), changes in thylakoid complexes, decreased photosynthetic activity and modifications in structure and functions of chloroplasts etc. Various defense mechanisms are triggered inside the plants in response to these stresses that are regulated by plant hormones or plant growth regulators. These phytohormones include abscisic acid, auxins, cytokinins, ethylene, brassinosteroids, jasmonates and salicylic acid etc. The present review focuses on stress protective effects of plants hormones on the photosynthetic responses.

  4. Xenohormesis: health benefits from an eon of plant stress response evolution

    PubMed Central

    Hooper, Paul L.; Tytell, Michael; Vígh, Lászlo

    2010-01-01

    Xenohormesis is a biological principle that explains how environmentally stressed plants produce bioactive compounds that can confer stress resistance and survival benefits to animals that consume them. Animals can piggyback off products of plants' sophisticated stress response which has evolved as a result of their stationary lifestyle. Factors eliciting the plant stress response can judiciously be employed to maximize yield of health-promoting plant compounds. The xenohormetic plant compounds can, when ingested, improve longevity and fitness by activating the animal's cellular stress response and can be applied in drug discovery, drug production, and nutritional enhancement of diet. PMID:20524162

  5. Exposed to events that never happen: Generalized unsafety, the default stress response, and prolonged autonomic activity.

    PubMed

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

    2017-03-01

    Based on neurobiological and evolutionary arguments, the generalized unsafety theory of stress (GUTS) hypothesizes that the stress response is a default response, and that chronic stress responses are caused by generalized unsafety (GU), independent of stressors or their cognitive representation. Three highly prevalent conditions are particularly vulnerable to becoming 'compromised' in terms of GU, and carry considerable health risks: Thus, GUTS critically revises and expands stress theory, by focusing on safety instead of threat, and by including risk factors that have hitherto not been attributed to stress.

  6. Adipocytes cause leukemia cell resistance to daunorubicin via oxidative stress response

    PubMed Central

    Sheng, Xia; Tucci, Jonathan; Parmentier, Jean-Hugues; Ji, Lingyun; Behan, James W.; Heisterkamp, Nora; Mittelman, Steven D.

    2016-01-01

    Adipocytes promote cancer progression and impair treatment, and have been shown to protect acute lymphoblastic leukemia (ALL) cells from chemotherapies. Here we investigate whether this protection is mediated by changes in oxidative stress. Co-culture experiments showed that adipocytes protect ALL cells from oxidative stress induced by drugs or irradiation. We demonstrated that ALL cells induce intracellular ROS and an oxidative stress response in adipocytes. This adipocyte oxidative stress response leads to the secretion of soluble factors which protect ALL cells from daunorubicin (DNR). Collectively, our investigation shows that ALL cells elicit an oxidative stress response in adipocytes, leading to adipocyte protection of ALL cells against DNR. PMID:27705905

  7. Decipher the Molecular Response of Plant Single Cell Types to Environmental Stresses

    PubMed Central

    2016-01-01

    The analysis of the molecular response of entire plants or organs to environmental stresses suffers from the cellular complexity of the samples used. Specifically, this cellular complexity masks cell-specific responses to environmental stresses and logically leads to the dilution of the molecular changes occurring in each cell type composing the tissue/organ/plant in response to the stress. Therefore, to generate a more accurate picture of these responses, scientists are focusing on plant single cell type approaches. Several cell types are now considered as models such as the pollen, the trichomes, the cotton fiber, various root cell types including the root hair cell, and the guard cell of stomata. Among them, several have been used to characterize plant response to abiotic and biotic stresses. In this review, we are describing the various -omic studies performed on these different plant single cell type models to better understand plant cell response to biotic and abiotic stresses. PMID:27088086

  8. Decipher the Molecular Response of Plant Single Cell Types to Environmental Stresses

    SciTech Connect

    Nourbakhsh-Rey, Mehrnoush; Libault, Marc

    2016-01-01

    The analysis of the molecular response of entire plants or organs to environmental stresses suffers from the cellular complexity of the samples used. Specifically, this cellular complexity masks cell-specific responses to environmental stresses and logically leads to the dilution of the molecular changes occurring in each cell type composing the tissue/organ/plant in response to the stress. Therefore, to generate a more accurate picture of these responses, scientists are focusing on plant single cell type approaches. Several cell types are now considered as models such as the pollen, the trichomes, the cotton fiber, various root cell types including the root hair cell, and the guard cell of stomata. Among them, several have been used to characterize plant response to abiotic and biotic stresses. Lastly, in this review, we are describing the various -omic studies performed on these different plant single cell type models to better understand plant cell response to biotic and abiotic stresses.

  9. Plasma omega 3 polyunsaturated fatty acid status and monounsaturated fatty acids are altered by chronic social stress and predict endocrine responses to acute stress in titi monkeys

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Disturbances in fatty acid (FA) metabolism may link chronic psychological stress, endocrine responsiveness, and psychopathology. Therefore, lipid metabolome-wide responses and their relationships with endocrine (cortisol; insulin; adiponectin) responsiveness to acute stress (AS) were assessed in a ...

  10. Adaptation or Malignant Transformation: The Two Faces of Epigenetically Mediated Response to Stress

    PubMed Central

    Zoldoš, Vlatka

    2013-01-01

    Adaptive response to stress is a fundamental property of living systems. At the cellular level, many different types of stress elicit an essentially limited repertoire of adaptive responses. Epigenetic changes are the main mechanism for medium- to long-term adaptation to accumulated (intense, long-term, or repeated) stress. We propose the adaptive deregulation of the epigenome in response to stress (ADERS) hypothesis which assumes that the unspecific adaptive stress response grows stronger with the increasing stress level, epigenetically activating response gene clusters while progressively deregulating other cellular processes. The balance between the unspecific adaptive response and the general epigenetic deregulation is critical because a strong response can lead to pathology, particularly to malignant transformation. The main idea of our hypothesis is the continuum traversed by a cell subjected to accumulated stress, which lies between an unspecific adaptive response and pathological deregulation—the two extremes sharing the same underlying cause, which is a manifestation of a unified epigenetically mediated adaptive response to stress. The evolutionary potential of epigenetic regulation in multigenerational adaptation is speculatively discussed in the light of neo-Lamarckism. Finally, an approach to testing the proposed hypothesis is presented, relying on either the publicly available datasets or on conducting new experiments. PMID:24187667

  11. Adaptation or malignant transformation: the two faces of epigenetically mediated response to stress.

    PubMed

    Vojta, Aleksandar; Zoldoš, Vlatka

    2013-01-01

    Adaptive response to stress is a fundamental property of living systems. At the cellular level, many different types of stress elicit an essentially limited repertoire of adaptive responses. Epigenetic changes are the main mechanism for medium- to long-term adaptation to accumulated (intense, long-term, or repeated) stress. We propose the adaptive deregulation of the epigenome in response to stress (ADERS) hypothesis which assumes that the unspecific adaptive stress response grows stronger with the increasing stress level, epigenetically activating response gene clusters while progressively deregulating other cellular processes. The balance between the unspecific adaptive response and the general epigenetic deregulation is critical because a strong response can lead to pathology, particularly to malignant transformation. The main idea of our hypothesis is the continuum traversed by a cell subjected to accumulated stress, which lies between an unspecific adaptive response and pathological deregulation--the two extremes sharing the same underlying cause, which is a manifestation of a unified epigenetically mediated adaptive response to stress. The evolutionary potential of epigenetic regulation in multigenerational adaptation is speculatively discussed in the light of neo-Lamarckism. Finally, an approach to testing the proposed hypothesis is presented, relying on either the publicly available datasets or on conducting new experiments.

  12. Hexavalent chromium induced stress and metabolic responses in hybrid willows.

    PubMed

    Yu, Xiao-Zhang; Gu, Ji-Dong; Huang, Shen-Zhuo

    2007-04-01

    Metabolic responses to hexavalent chromium (Cr(6+)) stress and the uptake and translocation of Cr(6+ )were investigated using pre-rooted hybrid willows (Salix matsudana Koidz x Salix alba L.) exposed to hydroponic solution spiked with K(2)CrO(4) at 24.0 +/- 1 degrees C for 192 h. Various physiological parameters of the plants were monitored to determine toxicity from Cr(6+ )exposure. At Cr(6+) treatments of 50% higher than that of the non-treated control plants. As Cr concentrations were increased further, a slight increase in the transpiration rate was also observed compared with the controls. Negligible difference in the chlorophyll contents in leaves between the treated and the non-treated control plants was measured, except for willows exposed to 1.05 mg Cr/l. The response of soluble proteins in leaves of willows to Cr treatments was remarkable. Cr-induced toxicity appeared in all treatments resulting in reduced activities of catalase (CAT) and peroxidase (POD) compared to the controls. Superoxide dismutases (SOD) activity in the leaf cells showed a positive increase after Cr exposure. Of all selected parameters, soluble proteins in leaves were the most sensitive to Cr(6+ )doses, showing a significant linear correlation negatively (R (2) = 0.931). Uptake of Cr(6+) by willows grown in flasks was found to increase linearly with the added Cr(6+ )(a zero order kinetics), as indicated by the high R (2) (0.9322). Recovery of Cr in different parts of plant materials varied significantly with roots being the dominant site of Cr accumulation. Although the translocation to shoots was detected, the amount of Cr translocated to shoots was considerably small. The capacity of willows to assimilate Cr(6+ )was also evaluated using detached leaves and roots in sealed glass vessels in vivo. Uptake of Cr by roots was mediated possibly through an active transport mechanism, whereas the cuticle of leaves was the major obstacle

  13. Stress for invasion success? Temperature stress of preceding generations modifies the response to insecticide stress in an invasive pest insect

    PubMed Central

    Piiroinen, Saija; Lyytinen, Anne; Lindström, Leena

    2013-01-01

    Adaptation to stressful environments is one important factor influencing species invasion success. Tolerance to one stress may be complicated by exposure to other stressors experienced by the preceding generations. We studied whether parental temperature stress affects tolerance to insecticide in the invasive Colorado potato beetle Leptinotarsa decemlineata. Field-collected pyrethroid-resistant beetles were reared under either stressful (17°C) or favourable (23°C) insecticide-free environments for three generations. Then, larvae were exposed to pyrethroid insecticides in common garden conditions (23°C). Beetles were in general tolerant to stress. The parental temperature stress alone affected beetles positively (increased adult weight) but it impaired their tolerance to insecticide exposure. In contrast, offspring from the favourable temperature regime showed compensatory weight gain in response to insecticide exposure. Our study emphasizes the potential of cross-generational effects modifying species stress tolerance. When resistant pest populations invade benign environments, a re-application of insecticides may enhance their performance via hormetic effects. In turn, opposite effects may arise if parental generations have been exposed to temperature stress. Thus, the outcome of management practices of invasive pest species is difficult to predict unless we also incorporate knowledge of the evolutionary and recent (preceding generations) stress history of the given populations into pest management. PMID:23467574

  14. Vascular heat shock protein expression in response to stress. Endocrine and autonomic regulation of this age-dependent response.

    PubMed Central

    Udelsman, R; Blake, M J; Stagg, C A; Li, D G; Putney, D J; Holbrook, N J

    1993-01-01

    Adaptation to stress requires coordinated interactions between the vascular and endocrine systems. Previously we demonstrated that restraint stress induces the expression of the major heat shock protein, HSP70, in the adrenal cortex of the rat. Here we demonstrate that restraint also induces expression of HSP70 in the vasculature. We further demonstrate that the adrenal and vascular responses are differentially regulated: the adrenal response is adrenocorticotropin dependent, whereas the vascular response is under adrenergic control. In addition, the adrenal response is restricted to members of the HSP70 gene family, whereas in vascular tissue the low molecular weight HSP, HSP27, is also induced by restraint. Further characterization of the vascular response revealed that HSP70 induction occurred in both the thoracic and abdominal aortas as well as in the vena cava. However, no HSP70 induction was apparent in the heart or in a wide variety of other tissues examined. In situ hybridization showed that the vascular expression was localized to the aortic smooth muscle cells with minimal expression in the endothelium. Induction of HSP70 mRNA in both the adrenal cortex and aorta was followed by an elevation in HSP70 protein. Maximum HSP70 protein levels were seen within 3-12 h after restraint, but declined thereafter. Stress induced HSP70 expression was dramatically reduced with age, which may explain, in part, the diminished tolerance to stress seen in elderly individuals. Images PMID:8094399

  15. Repeatability of cortisol stress response in the European sea bass (Dicentrarchus labrax) and transcription differences between individuals with divergent responses

    PubMed Central

    Samaras, A.; Dimitroglou, A.; Sarropoulou, E.; Papaharisis, L.; Kottaras, L.; Pavlidis, M.

    2016-01-01

    Understanding the stress responses of organisms is of importance in the performance and welfare of farmed animals, including fish. Especially fish in aquaculture commonly face stressors, and better knowledge of their responses may assist in proper husbandry and selection of breeding stocks. European sea bass (Dicentrarchus labrax), a species with high cortisol concentrations, is of major importance in this respect. The main objectives of the present study were to assess the repeatability and consistency of cortisol stress response and to identify differences in liver transcription profiles of European sea bass individuals, showing a consistent low (LR) or high (HR) cortisol response. The progeny of six full sib families was used, and sampled for plasma cortisol after an acute stress challenge once per month, for four consecutive months. Results suggest that cortisol responsiveness was a repeatable trait with LR and HR fish showing low or high resting, free and post-stress cortisol concentrations respectively. Finally, the liver transcription profiles of LR and HR fish showed some important differences, indicating differential hepatic regulation between these divergent phenotypes. These transcription differences were related to various metabolic and immunological processes, with 169 transcripts being transcribed exclusively in LR fish and 161 exclusively in HR fish. PMID:27703277

  16. Cortisol Response to Stress in Adults with Attention Deficit Hyperactivity Disorder

    PubMed Central

    Palomar, Gloria; Ferrer, Roser; Real, Alberto; Nogueira, Mariana; Corrales, Montserrat; Casas, Miguel; Ramos-Quiroga, Josep Antoni

    2015-01-01

    Background: Differences in the cortisol response have been reported between children exhibiting the inattentive and hyperactive/impulsive subtypes of attention deficit hyperactivity disorder. However, there is no such information about adults. The aim of the present study was to determine the possible differences between the combined and inattentive subtypes in the cortisol response to stress. Methods: Ninety-six adults with attention deficit hyperactivity disorder, 38 inattentive and 58 combined, without any medical or psychiatric comorbidities and 25 healthy controls were included. The Trier Social Stress Test was used to assess physiological stress responses. Clinical data and subjective stress levels, including the Perceived Stress Scale, were also recorded. Results: No significant differences in the cortisol response to the Trier Social Stress Test were found between patients and controls. However, albeit there were no basal differences, lower cortisol levels at 15 (P=.015), 30 (P=.015), and 45 minutes (P=.045) were observed in the combined compared with the inattentive subtype after the stress induction; these differences disappeared 60 minutes after the stress. In contrast, the subjective stress responses showed significant differences between attention deficit hyperactivity disorder patients and controls (P<.001), but no differences were seen between attention deficit hyperactivity disorder subtypes. In turn, subjective stress measures, such as the Perceived Stress Scale, positively correlated with the whole cortisol stress response (P<.027). Conclusions: Both the combined and inattentive attention deficit hyperactivity disorder adults exhibited a normal cortisol response to stress when challenged. Nevertheless, the inattentive patients displayed a higher level of cortisol after stress compared with the combined patients. Despite the differences in the cortisol response, adults with attention deficit hyperactivity disorder reported high levels of subjective

  17. Toward understanding transcriptional regulatory networks in abiotic stress responses and tolerance in rice

    PubMed Central

    2012-01-01

    Abiotic stress causes loss of crop production. Under abiotic stress conditions, expression of many genes is induced, and their products have important roles in stress responses and tolerance. Progress has been made in understanding the biological roles of regulons in abiotic stress responses in rice. A number of transcription factors (TFs) regulate stress-responsive gene expression. OsDREB1s and OsDREB2s were identified as abiotic-stress responsive TFs that belong to the AP2/ERF family. Similar to Arabidopsis, these DREB regulons were most likely not involved in the abscisic acid (ABA) pathway. OsAREBs such as OsAREB1 were identified as key components in ABA-dependent transcriptional networks in rice. OsNAC/SNACs including OsNAC6 were characterized as factors that regulate expression of genes important for abiotic stress responses in rice. Here, we review on the rice abiotic-stress responses mediated by transcriptional networks, with the main focus on TFs that function in abiotic stress responses and confer stress tolerance in rice. PMID:24764506

  18. Regulation of water, salinity, and cold stress responses by salicylic acid.

    PubMed

    Miura, Kenji; Tada, Yasuomi

    2014-01-01

    Salicylic acid (SA) is a naturally occurring phenolic compound. SA plays an important role in the regulation of plant growth, development, ripening, and defense responses. The role of SA in the plant-pathogen relationship has been extensively investigated. In addition to defense responses, SA plays an important role in the response to abiotic stresses, including drought, low temperature, and salinity stresses. It has been suggested that SA has great agronomic potential to improve the stress tolerance of agriculturally important crops. However, the utility of SA is dependent on the concentration of the applied SA, the mode of application, and the state of the plants (e.g., developmental stage and acclimation). Generally, low concentrations of applied SA alleviate the sensitivity to abiotic stresses, and high concentrations of applied induce high levels of oxidative stress, leading to a decreased tolerance to abiotic stresses. In this article, the effects of SA on the water stress responses and regulation of stomatal closure are reviewed.

  19. Gender differences in acculturation, stress, and salivary cortisol response among former Soviet immigrants.

    PubMed

    Nicholson, Lisa M; Miller, Arlene Michaels; Schwertz, Dorie; Sorokin, Olga

    2013-06-01

    Post-immigration adaptation is characterized by chronic and acute acculturative stressors. Salivary cortisol is a commonly used hormonal marker of stress, but few studies have investigated its use as an indicator of acculturative stress and adjustment in immigrants. The purpose of this study was to examine relationships among predictors of adjustment (environmental and language mastery), self-reported stress outcomes (depressive symptoms, perceived stress, alienation), and salivary cortisol response in immigrants from the former Soviet Union. The sample included 137 married men and women aged 42-80 who lived in the U.S. for 1-13 years. Results indicated that while men and women had similar values for cortisol response, relationships among adjustment measures, stress outcomes, and cortisol differed by gender. Among men, environmental mastery significantly reduced depressive symptoms, perceived stress, and cortisol response. Among women, environmental mastery also reduced depressive symptoms, perceived stress, and alienation, but language mastery increased cortisol response and decreased alienation.

  20. Stress responses as determinants of antimicrobial resistance in Gram-negative bacteria.

    PubMed

    Poole, Keith

    2012-05-01

    Bacteria encounter a myriad of potentially growth-compromising conditions in nature and in hosts of pathogenic bacteria. These 'stresses' typically elicit protective and/or adaptive responses that serve to enhance bacterial survivability. Because they impact upon many of the same cellular components and processes that are targeted by antimicrobials, adaptive stress responses can influence antimicrobial susceptibility. In targeting and interfering with key cellular processes, antimicrobials themselves are 'stressors' to which protective stress responses have also evolved. Cellular responses to nutrient limitation (nutrient stress), oxidative and nitrosative stress, cell envelope damage (envelope stress), antimicrobial exposure and other growth-compromising stresses, have all been linked to the development of antimicrobial resistance in Gram-negative bacteria - resulting from the stimulation of protective changes to cell physiology, activation of resistance mechanisms, promotion of resistant lifestyles (biofilms), and induction of resistance mutations.

  1. The calcium channel blocker verapamil inhibits oxidative stress response in Candida albicans.

    PubMed

    Yu, Qilin; Xiao, Chenpeng; Zhang, Kailun; Jia, Chang; Ding, Xiaohui; Zhang, Bing; Wang, Yu; Li, Mingchun

    2014-04-01

    Candida albicans is a common opportunistic fungal pathogen, causing both superficial candidiasis and life-threatening systemic infections in immune-compromised individuals. Calcium signaling is responsible for this pathogen in responding to several stresses, such as antifungal drugs, alkaline pH and membrane-perturbing agents. Our recent study revealed that it is also involved in oxidative stress response. In this study, we investigated the effect of verapamil, an L-type voltage-gated calcium channel blocker, on oxidative stress response in this fungus. The addition of verapamil resulted in increased sensitivity to the oxidative agent H2O2, which is associated with a decrease of calcium fluctuation under the stress. Moreover, this agent caused enhanced oxidative stress, with increased levels of ROS and enhanced dysfunction of the mitochondria under the oxidative stress. Further investigations in SOD activity, GSH contents and expression of oxidative stress response-related genes indicated that the effect of verapamil is related to the repression of oxidative stress response. Our findings demonstrated that verapamil has an inhibitory effect on oxidative stress response, confirming the relationship between calcium signaling and oxidative stress in C. albicans. Therefore, calcium channels may be potential targets for therapy to enhance the efficacy of oxidative stress against C. albicans-related infections.

  2. Influence of low level maternal Pb exposure and prenatal stress on offspring stress challenge responsivity.

    PubMed

    Virgolini, M B; Rossi-George, A; Weston, D; Cory-Slechta, D A

    2008-11-01

    We previously demonstrated potentiated effects of maternal Pb exposure producing blood Pb(PbB) levels averaging 39microg/dl combined with prenatal restraint stress (PS) on stress challenge responsivity of female offspring as adults. The present study sought to determine if: (1) such interactions occurred at lower PbBs, (2) exhibited gender specificity, and (3) corticosterone and neurochemical changes contributed to behavioral outcomes. Rat dams were exposed to 0, 50 or 150ppm Pb acetate drinking water solutions from 2 mos prior to breeding through lactation (pup exposure ended at weaning; mean PbBs of dams at weaning were <1, 11 and 31microg/dl, respectively); a subset in each Pb group underwent prenatal restraint stress (PS) on gestational days 16-17. The effects of variable intermittent stress challenge (restraint, cold, novelty) on Fixed Interval (FI) schedule controlled behavior and corticosterone were examined in offspring when they were adults. Corticosterone changes were also measured in non-behaviorally tested (NFI) littermates. PS alone was associated with FI rate suppression in females and FI rate enhancement in males; Pb exposure blunted these effects in both genders, particularly following restraint stress. PS alone produced modest corticosterone elevation following restraint stress in adult females, but robust enhancements in males following all challenges. Pb exposure blunted these corticosterone changes in females, but further enhanced levels in males. Pb-associated changes showed linear concentration dependence in females, but non-linearity in males, with stronger or selective changes at 50ppm. Statistically, FI performance was associated with corticosterone changes in females, but with frontal cortical dopaminergic and serotonergic changes in males. Corticosterone changes differed markedly in FI vs. NFI groups in both genders, demonstrating a critical role for behavioral history and raising caution about extrapolating biochemical markers across

  3. Assessing Stress Responses in Beaked and Sperm Whales in the Bahamas

    DTIC Science & Technology

    2012-09-30

    Wasser, S.K. 2012. Distinguishing the impacts of inadequate prey and vessel traffic on an endangered killer whale (Orcinus orca) population. PLoS One...1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Assessing Stress Responses in Beaked and Sperm Whales ...hormone assays to assess stress responses in Blainville’s beaked whales (Mesoplodon densirostris) and sperm whales (Physeter macrocephalus

  4. The Contribution of Deficits in Emotional Clarity to Stress Responses and Depression

    ERIC Educational Resources Information Center

    Flynn, Megan; Rudolph, Karen D.

    2010-01-01

    This research investigated the contribution of deficits in emotional clarity to children's socioemotional adjustment. Specifically, this study examined the proposal that deficits in emotional clarity are associated with maladaptive interpersonal stress responses, and that maladaptive interpersonal stress responses act as a mechanism linking…

  5. The Effects of Behavior Therapy, Self-Relaxation, and Transcendental Meditation on Cardiovascular Stress Response.

    ERIC Educational Resources Information Center

    Puente, Antonio E.; Beiman, Irving

    1980-01-01

    Compared Behavior Therapy (BT), self-relaxation (SR), transcendental meditation (TM), and a waiting-list control group (WL) on measures of cardiovascular and subjective stress response. Results indicate that BT and SR were more effective than either TM or WL in reducing cardiovascular stress response. (Author)

  6. Thermal stress and predation risk trigger distinct transcriptomic responses in the intertidal snail Nucella lapillus.

    PubMed

    Chu, Nathaniel D; Miller, Luke P; Kaluziak, Stefan T; Trussell, Geoffrey C; Vollmer, Steven V

    2014-12-01

    Thermal stress and predation risk have profound effects on rocky shore organisms, triggering changes in their feeding behaviour, morphology and metabolism. Studies of thermal stress have shown that underpinning such changes in several intertidal species are specific shifts in gene and protein expression (e.g. upregulation of heat-shock proteins). But relatively few studies have examined genetic responses to predation risk. Here, we use next-generation RNA sequencing (RNA-seq) to examine the transcriptomic (mRNA) response of the snail Nucella lapillus to thermal stress and predation risk. We found that like other intertidal species, N. lapillus displays a pronounced genetic response to thermal stress by upregulating many heat-shock proteins and other molecular chaperones. In contrast, the presence of a crab predator (Carcinus maenas) triggered few significant changes in gene expression in our experiment, and this response showed no significant overlap with the snail's response to thermal stress. These different gene expression profiles suggest that thermal stress and predation risk could pose distinct and potentially additive challenges for N. lapillus and that genetic responses to biotic stresses such as predation risk might be more complex and less uniform across species than genetic responses to abiotic stresses such as thermal stress.

  7. Respiratory Syncytial Virus and Cellular Stress Responses: Impact on Replication and Physiopathology

    PubMed Central

    Cervantes-Ortiz, Sandra L.; Zamorano Cuervo, Natalia; Grandvaux, Nathalie

    2016-01-01

    Human respiratory syncytial virus (RSV), a member of the Paramyxoviridae family, is a major cause of severe acute lower respiratory tract infection in infants, elderly and immunocompromised adults. Despite decades of research, a complete integrated picture of RSV-host interaction is still missing. Several cellular responses to stress are involved in the host-response to many virus infections. The endoplasmic reticulum stress induced by altered endoplasmic reticulum (ER) function leads to activation of the unfolded-protein response (UPR) to restore homeostasis. Formation of cytoplasmic stress granules containing translationally stalled mRNAs is a means to control protein translation. Production of reactive oxygen species is balanced by an antioxidant response to prevent oxidative stress and the resulting damages. In recent years, ongoing research has started to unveil specific regulatory interactions of RSV with these host cellular stress responses. Here, we discuss the latest findings regarding the mechanisms evolved by RSV to induce, subvert or manipulate the ER stress, the stress granule and oxidative stress responses. We summarize the evidence linking these stress responses with the regulation of RSV replication and the associated pathogenesis. PMID:27187445

  8. Abscisic Acid Elicits the Water-Stress Response in Root Hairs of Arabidopsis thaliana1

    PubMed Central

    Schnall, Jennifer A.; Quatrano, Ralph S.

    1992-01-01

    Water stress has been shown to cause root hairs to become short and bulbous. Because abscisic acid (ABA) mediates a variety of water-stress responses, we investigated the response of Arabidopsis thaliana root hairs to ABA. When wild-type root hairs were treated with ABA, they exhibited the water-stress response. The Arabidopsis mutants abi1 and abi2, which are insensitive to ABA at the seedling stage, did not display the root hair response. These data suggest that ABA may mediate the response of root hairs to water stress. The drought response of root hairs resulting in an inhibition of tip growth will provide an easy screen to select mutations that are insensitive to ABA and/or involved in tip growth. Images Figure 1 PMID:16652949

  9. Impulsivity and Stress Response in Pathological Gamblers During the Trier Social Stress Test.

    PubMed

    Maniaci, G; Goudriaan, A E; Cannizzaro, C; van Holst, R J

    2017-03-18

    Gambling has been associated with increased sympathetic nervous system output and stimulation of the hypothalamic-pituitary-adrenal axis. However it is unclear how these systems are affected in pathological gambling. This study aimed to investigate the effect of the Trier Social Stress Test (TSST) on cortisol and on cardiac interbeat intervals in relation to impulsivity, in a sample of male pathological gamblers compared to healthy controls. In addition, we investigated the correlation between the TSST, duration of the disorder and impulsivity. A total of 35 pathological gamblers and 30 healthy controls, ranging from 19 to 58 years old and all male, participated in this study. Stress response was measured during and after the TSST by salivary cortisol and cardiac interbeat intervals; impulsivity was assessed with the Barratt Impulsiveness Scale (BIS-11). Exposure to the TSST produced a significant increase in salivary cortisol and interbeat intervals in both groups, without differences between groups. We found a negative correlation between baseline cortisol and duration of pathological gambling indicating that the longer the duration of the disorder the lower the baseline cortisol levels. Additionally, we found a main effect of impulsivity across groups on interbeat interval during the TSST, indicating an association between impulsivity and the intensity of the neurovegetative stress response during the TSST. Involvement of the hypothalamic-pituitary-adrenal axis in pathological gambling was confirmed together with evidence of a correlation between length of the disorder and diminished baseline cortisol levels. Impulsivity emerged as a personality trait expressed by pathological gamblers; however the neurovegetative response to the TSST, although associated with impulsivity, appeared to be independent of the presence of pathological gambling.

  10. Allopregnanolone and social stress: regulation of the stress response in early pregnancy in pigs.

    PubMed

    Rault, Jean-Loup; Plush, Kate; Yawno, Tamara; Langendijk, Pieter

    2015-01-01

    This experiment investigated whether allopregnanolone, a neurosteroid metabolite from progesterone, modulates the stress response during early pregnancy. Twenty-five nulliparous sows (Sus scrofa) were allocated to one of three treatments: pregnant, ovariectomized or ovariectomized administered daily intravenously with alfaxalone as a synthetic allopregnanolone analog. On days 5, 12 and 19 of pregnancy, all sows were subjected to social stress by submitting them individually to a resident-intruder test, acting as the intruder. Blood samples were collected to analyze plasma progesterone, allopregnanolone, cortisol and adrenocorticotropic hormone (ACTH) concentrations. On day 26, 10 sows across the three treatments were subjected to a dexamethasone suppression test followed by a corticotrophin-releasing hormone administration to test the functionality of their hypothalamo-pituitary-adrenal (HPA) axis through cortisol release. Pregnant sows returned more rapidly to baseline cortisol concentrations following the resident-intruder test (p = 0.006). However, there were no other differences in cortisol or ACTH concentrations according to treatment or day, or to the HPA responsivity test on day 26. Allopregnanolone concentration in pregnant sows was higher than in ovariectomized sows (p < 0.001), but stable during the first third of pregnancy. Allopregnanolone concentration was correlated with longer resident-intruder test duration (pregnant: r = 0.66, p = 0.0003; ovariectomized: r = 0.47, p = 0.03), reflecting lower aggressiveness, and with progesterone concentration (r = 0.25, p = 0.03). Alfaxalone administration raised plasma allopregnanolone concentration in alfaxalone-administered sows but resulted in little behavioral and physiological effects. These findings did not support the hypothesis that the stress response of the female pig changes in the first third of pregnancy. Allopregnanolone was associated with lower aggression in social

  11. Natural variations in the stress and acute phase responses of cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The initial response of the innate immune system upon activation has been defined as the acute phase response (APR). Activation of the APR results in several responses that include fever, metabolic adaptations, and changes in behavior. The APR can be modulated by many factors, with stress being th...

  12. Arabidopsis seed germination responses to osmotic stress involve the chromatin modifier PICKLE.

    PubMed

    Belin, Christophe; Lopez-Molina, Luis

    2008-07-01

    pkl mutant seed germination is hypersensitive to ABA treatment due to abnormally high and persistent ABI3 and ABI5 expression. PKL, a putative chromatin modifier, is instrumental to associate ABI3 and ABI5 with silent chromatin in response to ABA. Thus, PKL prevents exaggerated germination arrest responses by shutting off ABI3 and ABI5 expression in response to mild stresses.

  13. Gene expression changes in response to aging compared to heat stress, oxidative stress and ionizing radiation in Drosophila melanogaster.

    PubMed

    Landis, Gary; Shen, Jie; Tower, John

    2012-11-01

    Gene expression changes in response to aging, heat stress, hyperoxia, hydrogen peroxide, and ionizing radiation were compared using microarrays. A set of 18 genes were up-regulated across all conditions, indicating a general stress response shared with aging, including the heat shock protein (Hsp) genes Hsp70, Hsp83 and l(2)efl, the glutathione-S-transferase gene GstD2, and the mitochondrial unfolded protein response (mUPR) gene ref(2)P. Selected gene expression changes were confirmed using quantitative PCR, Northern analysis and GstD-GFP reporter constructs. Certain genes were altered in only a subset of the conditions, for example, up-regulation of numerous developmental pathway and signaling genes in response to hydrogen peroxide. While aging shared features with each stress, aging was more similar to the stresses most associated with oxidative stress (hyperoxia, hydrogen peroxide, ionizing radiation) than to heat stress. Aging is associated with down-regulation of numerous mitochondrial genes, including electron-transport-chain (ETC) genes and mitochondrial metabolism genes, and a sub-set of these changes was also observed upon hydrogen peroxide stress and ionizing radiation stress. Aging shared the largest number of gene expression changes with hyperoxia. The extensive down-regulation of mitochondrial and ETC genes during aging is consistent with an aging-associated failure in mitochondrial maintenance, which may underlie the oxidative stress-like and proteotoxic stress-like responses observed during aging.

  14. Infants, mothers, and dyadic contributions to stability and prediction of social stress response at 6 months.

    PubMed

    Provenzi, Livio; Olson, Karen L; Montirosso, Rosario; Tronick, Ed

    2016-01-01

    The study of infants' interactive style and social stress response to repeated stress exposures is of great interest for developmental and clinical psychologists. Stable maternal and dyadic behavior is critical to sustain infants' development of an adaptive social stress response, but the association between infants' interactive style and social stress response has received scant attention in previous literature. In the present article, overtime stability of infant, maternal, and dyadic behaviors was measured across 2 social stress (i.e., Face-to-Face Still-Face, FFSF) exposures, separated by 15 days. Moreover, infant, maternal, and dyadic behaviors were simultaneously assessed as predictors of infants' social stress to both FFSF exposures. Eighty-one mother-infant dyads underwent the FFSF twice, at 6 months (Exposure 1: the first social stress) and at 6 months and 15 days (Exposure 2: repeated social stress). Infant and mother behavior and dyadic synchrony were microanalytically coded. Overall, individual behavioral stability emerged between FFSF exposures. Infants' response to the first stress was predicted by infant behavior during Exposure 1 Play. Infants' response to the repeated social stress was predicted by infants' response to the first exposure to the Still-Face and by infants' behavior and dyadic synchrony during Exposure 2 Play. Findings reveal stability for individual, but not for dyadic, behavior between 2 social stress exposures at 6 months. Infants' response to repeated social stress was predicted by infants' earlier stress response, infants' own behavior in play, and dyadic synchrony. No predictive effects of maternal behavior were found. Insights for research and clinical work are discussed.

  15. Renal sympathetic nerve, blood flow, and epithelial transport responses to thermal stress.

    PubMed

    Wilson, Thad E

    2017-05-01

    Thermal stress is a profound sympathetic stress in humans; kidney responses involve altered renal sympathetic nerve activity (RSNA), renal blood flow, and renal epithelial transport. During mild cold stress, RSNA spectral power but not total activity is altered, renal blood flow is maintained or decreased, and epithelial transport is altered consistent with a sympathetic stress coupled with central volume loaded state. Hypothermia decreases RSNA, renal blood flow, and epithelial transport. During mild heat stress, RSNA is increased, renal blood flow is decreased, and epithelial transport is increased consistent with a sympathetic stress coupled with a central volume unloaded state. Hyperthermia extends these directional changes, until heat illness results. Because kidney responses are very difficult to study in humans in vivo, this review describes and qualitatively evaluates an in vivo human skin model of sympathetically regulated epithelial tissue compared to that of the nephron. This model utilizes skin responses to thermal stress, involving 1) increased skin sympathetic nerve activity (SSNA), decreased skin blood flow, and suppressed eccrine epithelial transport during cold stress; and 2) increased SSNA, skin blood flow, and eccrine epithelial transport during heat stress. This model appears to mimic aspects of the renal responses. Investigations of skin responses, which parallel certain renal responses, may aid understanding of epithelial-sympathetic nervous system interactions during cold and heat stress.

  16. Heat stress responses modulate calcium regulations and electrophysiological characteristics in atrial myocytes.

    PubMed

    Chen, Yao-Chang; Kao, Yu-Hsun; Huang, Chun-Feng; Cheng, Chen-Chuan; Chen, Yi-Jen; Chen, Shih-Ann

    2010-04-01

    Heat stress-induced responses change the ionic currents and calcium homeostasis. However, the molecular insights into the heat stress responses on calcium homeostasis remain unclear. The purposes of this study were to examine the mechanisms of heat stress responses on calcium handling and electrophysiological characteristics in atrial myocytes. We used indo-1 fluorimetric ratio technique and whole-cell patch clamp to investigate the intracellular calcium, action potentials, and ionic currents in isolated rabbit single atrial cardiomyocytes with or without (control) exposure to heat stress (43 degrees C, 15 min) 5+/-1 h before experiments. The expressions of sarcoplasmic reticulum ATPase (SERCA2a), and Na(+)-Ca(2+) exchanger (NCX) in the control and heat stress-treated atrial myocytes were evaluated by Western blot and real-time PCR. As compared with control myocytes, the heat stress-treated myocytes had larger sarcoplasmic reticulum calcium content and larger intracellular calcium transient with a shorter decay portion. Heat stress-treated myocytes also had larger L-type calcium currents, transient outward potassium currents, but smaller NCX currents. Heat stress responses increased the protein expressions, SERCA2a, NCX, and heat shock protein. However, heat stress responses did not change the RNA expression of SERCA2a and NCX. In conclusion, heat stress responses change calcium handling through protein but not RNA regulation.

  17. Changes in hypothalamic-pituitary-adrenal stress responsiveness before and after puberty in rats.

    PubMed

    Klein, Zoe A; Romeo, Russell D

    2013-07-01

    This article is part of a Special Issue "Puberty and Adolescence". Many endocrine changes are associated with pubertal and adolescent development. One such change is the responsiveness of the hypothalamic-pituitary-adrenal (HPA) axis to physical and/or psychological stressors. Recent human and non-human animal studies have shown that hormonal stress reactivity increases significantly throughout puberty and adolescence. Specifically, exposure to various stressors results in greater adrenocorticotropic hormone (ACTH) and glucocorticoid responses in peripubertal compared to adult animals. This review will focus on how stress reactivity changes throughout puberty and adolescence, as well as potential mechanisms that mediate these changes in stress responsiveness. Though the implications of these pubertal shifts in stress responsiveness are not fully understood, the significant increase in stress-related mental and physical dysfunctions during this stage of development highlights the importance of studying pubertal and adolescent maturation of HPA function and its reactivity to stress.

  18. Metabolic effects of chronic ACTH administration, interaction with response to stress.

    PubMed

    Armario, A; Campmany, L; Hidalgo, J

    1986-01-01

    The present experiment was undertaken to study the metabolic response to stress of single or chronic ACTH-treated male rats. It was found that chronic ACTH-treated rats showed a slight reduction in food intake and a decrease in body weight gain. This treatment increased basal serum triglyceride and insulin levels. In addition, some differences in response to stress was found in chronic ACTH-treated rats. Thus, these latter animals, unlike the other two groups, showed a decrease in circulating triglyceride and insulin levels in response to short-term stress. Moreover, 24 h after onset of stress a more marked fall in liver weight and glucose levels were found in chronic ACTH-treated rats. It suggests that chronic ACTH treatment might alter the metabolic response to prolonged acute stress what could result in lower resistance to severe stresses.

  19. Dissecting the various responsive modes to drought stress responses in corn with contrasting tolerance to drought

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Drought decreases crop yield and exacerbates Aspergillus flavus infection resulting in pre-harvest aflatoxin contamination. Deciphering crop tolerance and adaptation to drought can contribute to the improvement of drought tolerance through breeding. In order to investigate the responsive modes in co...

  20. Transcriptional regulation of gene expression during osmotic stress responses by the mammalian target of rapamycin.

    PubMed

    Ortells, M Carmen; Morancho, Beatriz; Drews-Elger, Katherine; Viollet, Benoit; Laderoute, Keith R; López-Rodríguez, Cristina; Aramburu, Jose

    2012-05-01

    Although stress can suppress growth and proliferation, cells can induce adaptive responses that allow them to maintain these functions under stress. While numerous studies have focused on the inhibitory effects of stress on cell growth, less is known on how growth-promoting pathways influence stress responses. We have approached this question by analyzing the effect of mammalian target of rapamycin (mTOR), a central growth controller, on the osmotic stress response. Our results showed that mammalian cells exposed to moderate hypertonicity maintained active mTOR, which was required to sustain their cell size and proliferative capacity. Moreover, mTOR regulated the induction of diverse osmostress response genes, including targets of the tonicity-responsive transcription factor NFAT5 as well as NFAT5-independent genes. Genes sensitive to mTOR-included regulators of stress responses, growth and proliferation. Among them, we identified REDD1 and REDD2, which had been previously characterized as mTOR inhibitors in other stress contexts. We observed that mTOR facilitated transcription-permissive conditions for several osmoresponsive genes by enhancing histone H4 acetylation and the recruitment of RNA polymerase II. Altogether, these results reveal a previously unappreciated role of mTOR in regulating transcriptional mechanisms that control gene expression during cellular stress responses.

  1. Transcriptional regulation of gene expression during osmotic stress responses by the mammalian target of rapamycin

    PubMed Central

    Ortells, M. Carmen; Morancho, Beatriz; Drews-Elger, Katherine; Viollet, Benoit; Laderoute, Keith R.; López-Rodríguez, Cristina; Aramburu, Jose

    2012-01-01

    Although stress can suppress growth and proliferation, cells can induce adaptive responses that allow them to maintain these functions under stress. While numerous studies have focused on the inhibitory effects of stress on cell growth, less is known on how growth-promoting pathways influence stress responses. We have approached this question by analyzing the effect of mammalian target of rapamycin (mTOR), a central growth controller, on the osmotic stress response. Our results showed that mammalian cells exposed to moderate hypertonicity maintained active mTOR, which was required to sustain their cell size and proliferative capacity. Moreover, mTOR regulated the induction of diverse osmostress response genes, including targets of the tonicity-responsive transcription factor NFAT5 as well as NFAT5-independent genes. Genes sensitive to mTOR-included regulators of stress responses, growth and proliferation. Among them, we identified REDD1 and REDD2, which had been previously characterized as mTOR inhibitors in other stress contexts. We observed that mTOR facilitated transcription-permissive conditions for several osmoresponsive genes by enhancing histone H4 acetylation and the recruitment of RNA polymerase II. Altogether, these results reveal a previously unappreciated role of mTOR in regulating transcriptional mechanisms that control gene expression during cellular stress responses. PMID:22287635

  2. Moderation of physiological stress responses by personality traits and daily hassles: less flexibility of immune system responses.

    PubMed

    Peters, Madelon L; Godaert, Guido L R; Ballieux, Rudy E; Heijnen, Coby J

    2003-12-01

    Previously we demonstrated that stressors varying on the dimension of mental effort and controllability have distinctive effects on cardiovascular, endocrine and immune system responses. The purpose of the present study was to relate individual differences in physiological stress responsivity to task appraisal and stress-induced mood changes (issue 1), trait characteristics (issue 2) and daily hassles (issue 3). Appraisal and mood changes did not mediate the differential effects of the stressors. The trait characteristics, aggression and external locus of control and daily hassles moderated the effect of the stressor on physiological parameters, especially immune parameters. Moreover, the moderation effect was different in the high versus the low effort stress task. High aggression, high external locus of control and more daily hassles were associated with increased reactivity in the low effort condition and decreased reactivity in the high effort condition, which is suggested to reflect less differentiated responding to changing task demands and hence, less flexibility in the immune system.

  3. The Hippo pathway promotes cell survival in response to chemical stress

    PubMed Central

    Di Cara, F; Maile, T M; Parsons, B D; Magico, A; Basu, S; Tapon, N; King-Jones, K

    2015-01-01

    Cellular stress defense mechanisms have evolved to maintain homeostasis in response to a broad variety of environmental challenges. Stress signaling pathways activate multiple cellular programs that range from the activation of survival pathways to the initiation of cell death when cells are damaged beyond repair. To identify novel players acting in stress response pathways, we conducted a cell culture RNA interference (RNAi) screen using caffeine as a xenobiotic stress-inducing agent, as this compound is a well-established inducer of detoxification response pathways. Specifically, we examined how caffeine affects cell survival when Drosophila kinases and phosphatases were depleted via RNAi. Using this approach, we identified and validated 10 kinases and 4 phosphatases that are essential for cell survival under caffeine-induced stress both in cell culture and living flies. Remarkably, our screen yielded an enrichment of Hippo pathway components, indicating that this pathway regulates cellular stress responses. Indeed, we show that the Hippo pathway acts as a potent repressor of stress-induced cell death. Further, we demonstrate that Hippo activation is necessary to inhibit a pro-apoptotic program triggered by the interaction of the transcriptional co-activator Yki with the transcription factor p53 in response to a range of stress stimuli. Our in vitro and in vivo loss-of-function data therefore implicate Hippo signaling in the transduction of cellular survival signals in response to chemical stress. PMID:26021298

  4. Molecular response of Saccharomyces cerevisiae wine and laboratory strains to high sugar stress conditions.

    PubMed

    Jiménez-Martí, E; Zuzuarregui, A; Gomar-Alba, M; Gutiérrez, D; Gil, C; del Olmo, M

    2011-01-31

    One of the stress conditions that can affect Saccharomyces cerevisiae cells during their growth is osmotic stress. Under particular environments (for instance, during the production of alcoholic beverages) yeasts have to cope with osmotic stress caused by high sugar concentrations. Although the molecular changes and pathways involved in the response to saline or sorbitol stress are widely understood, less is known about how cells respond to high sugar concentrations. In this work we present a comprehensive study of the response to this form of stress which indicates important transcriptomic changes, especially in terms of the genes involved in both stress response and respiration, and the implication of the HOG pathway. We also describe several genes of an unknown function which are more highly expressed under 20% (w/v) glucose than under 2% (w/v) glucose. In this work we focus on the YHR087w (RTC3) gene and its encoded protein. Proteomic analysis of the mutant deletion strain reveals lower levels of several yeast Hsp proteins, which establishes a link between this protein and the response to several forms of stress. The relevance of YHR087W for the response to high sugar and other stress conditions and the relationship of the encoded protein with several Hsp proteins suggest applications of this gene in biotechnological processes in which response to stress is important.

  5. 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

  6. The essential biology of the endoplasmic reticulum stress response for structural and computational biologists

    PubMed Central

    Wakabayashi, Sadao; Yoshida, Hiderou

    2013-01-01

    The endoplasmic reticulum (ER) stress response is a cytoprotective mechanism that maintains homeostasis of the ER by upregulating the capacity of the ER in accordance with cellular demands. If the ER stress response cannot function correctly, because of reasons such as aging, genetic mutation or environmental stress, unfolded proteins accumulate in the ER and cause ER stress-induced apoptosis, resulting in the onset of folding diseases, including Alzheimer's disease and diabetes mellitus. Although the mechanism of the ER stress response has been analyzed extensively by biochemists, cell biologists and molecular biologists, many aspects remain to be elucidated. For example, it is unclear how sensor molecules detect ER stress, or how cells choose the two opposite cell fates (survival or apoptosis) during the ER stress response. To resolve these critical issues, structural and computational approaches will be indispensable, although the mechanism of the ER stress response is complicated and difficult to understand holistically at a glance. Here, we provide a concise introduction to the mammalian ER stress response for structural and computational biologists. PMID:24688718

  7. A robust and reliable non-invasive test for stress responsivity in mice

    PubMed Central

    Zimprich, Annemarie; Garrett, Lillian; Deussing, Jan M.; Wotjak, Carsten T.; Fuchs, Helmut; Gailus-Durner, Valerie; de Angelis, Martin Hrabě; Wurst, Wolfgang; Hölter, Sabine M.

    2014-01-01

    Stress and an altered stress response have been associated with many multifactorial diseases, such as psychiatric disorders or neurodegenerative diseases. As currently mouse mutants for each single gene are generated and phenotyped in a large-scale manner, it seems advisable also to test these mutants for alterations in their stress responses. Here we present the determinants of a robust and reliable non-invasive test for stress-responsivity in mice. Stress is applied through restraining the mice in tubes and recording behavior in the Open Field 20 min after cessation of the stress. Two hours, but not 15 or 50 min of restraint lead to a robust and reproducible increase in distance traveled and number of rearings during the first 5 min in the Open Field in C57BL/6 mice. This behavioral response is blocked by the corticosterone synthesis inhibitor metyrapone, but not by RU486 treatment, indicating that it depends on corticosteroid secretion, but is not mediated via the glucocorticoid receptor type II. We assumed that with a stress duration of 15 min one could detect hyper-responsivity, and with a stress duration of 2 h hypo-responsivity in mutant mouse lines. This was validated with two mutant lines known to show opposing effects on corticosterone secretion after stress exposure, corticotropin-releasing hormone (CRH) over-expressing mice and CRH receptor 1 knockout (KO) mice. Both lines showed the expected phenotype, i.e., increased stress responsivity in the CRH over-expressing mouse line (after 15 min restraint stress) and decreased stress responsivity in the CRHR1-KO mouse line (after 2 h of restraint stress). It is possible to repeat the acute stress test several times without the stressed animal adapting to it, and the behavioral response can be robustly evoked at different ages, in both sexes and in different mouse strains. Thus, locomotor and rearing behavior in the Open Field after an acute stress challenge can be used as reliable, non-invasive indicators of

  8. Absence of response: a study of nurses' experience of stress in the workplace.

    PubMed

    Olofsson, Brita; Bengtsson, Claire; Brink, Eva

    2003-09-01

    It has become clear that nursing is a high-risk occupation with regards to stress-related diseases. In this study, we were interested in nurses' experiences of stress and the emotions arising from stress at work. Results showed that nurses experienced negative stress which was apparently related to the social environment in which they worked. Four nurses were interviewed. The method used was grounded theory. Analysis of the interviews singled out absence of response as the core category. Recurring stressful situations obviously caused problems for the nurses in their daily work. Not only did they lack responses from their supervisors, they also experienced emotions of frustration, powerlessness, hopelessness and inadequacy, which increased the general stress experienced at work. Our conclusion is that the experience of absence of response leads to negative stress in nurses.

  9. Transposable Elements Contribute to Activation of Maize Genes in Response to Abiotic Stress

    PubMed Central

    Makarevitch, Irina; Waters, Amanda J.; West, Patrick T.; Stitzer, Michelle; Hirsch, Candice N.; Ross-Ibarra, Jeffrey; Springer, Nathan M.

    2015-01-01

    Transposable elements (TEs) account for a large portion of the genome in many eukaryotic species. Despite their reputation as “junk” DNA or genomic parasites deleterious for the host, TEs have complex interactions with host genes and the potential to contribute to regulatory variation in gene expression. It has been hypothesized that TEs and genes they insert near may be transcriptionally activated in response to stress conditions. The maize genome, with many different types of TEs interspersed with genes, provides an ideal system to study the genome-wide influence of TEs on gene regulation. To analyze the magnitude of the TE effect on gene expression response to environmental changes, we profiled gene and TE transcript levels in maize seedlings exposed to a number of abiotic stresses. Many genes exhibit up- or down-regulation in response to these stress conditions. The analysis of TE families inserted within upstream regions of up-regulated genes revealed that between four and nine different TE families are associated with up-regulated gene expression in each of these stress conditions, affecting up to 20% of the genes up-regulated in response to abiotic stress, and as many as 33% of genes that are only expressed in response to stress. Expression of many of these same TE families also responds to the same stress conditions. The analysis of the stress-induced transcripts and proximity of the transposon to the gene suggests that these TEs may provide local enhancer activities that stimulate stress-responsive gene expression. Our data on allelic variation for insertions of several of these TEs show strong correlation between the presence of TE insertions and stress-responsive up-regulation of gene expression. Our findings suggest that TEs provide an important source of allelic regulatory variation in gene response to abiotic stress in maize. PMID:25569788

  10. Cardiovascular and Affective Responses to Social Stress in Adolescents with Internalizing and Externalizing Problems

    ERIC Educational Resources Information Center

    Hastings, Paul D.; Zahn-Waxler, Carolyn; Usher, Barbara A.

    2007-01-01

    Behavioral responses to stress and challenge are based in emotional and physiological arousal reactions. Adolescents with maladaptive or problematic behavior patterns, such as internalizing or externalizing problems, are likely to show atypical emotional and physiological reactions to stress. Relations between problems and reactions to stress were…

  11. Conversion of psychological stress into cellular stress response: roles of the sigma-1 receptor in the process.

    PubMed

    Hayashi, Teruo

    2015-04-01

    Psychiatrists empirically recognize that excessive or chronic psychological stress can result in long-lasting impairments of brain functions that partly involve neuronal cell damage. Recent studies begin to elucidate the molecular pathways activated/inhibited by psychological stress. Activation of the hypothalamic-pituitary-adrenal axis under psychological stress causes inflammatory oxidative stresses in the brain, in part due to elevation of cytokines. Psychological stress or neuropathological conditions (e.g., accumulation of β-amyloids) trigger 'cellular stress responses', which promote upregulation of molecular chaperones to protect macromolecules from degradation. The unfolded protein response, the endoplasmic reticulum (ER)-specific cellular stress response, has been recently implicated in the pathophysiology of neuropsychiatric disorders and the pharmacology of certain clinically used drugs. The sigma-1 receptor is an ER protein whose ligands are shown to exert antidepressant-like and neuroprotective actions. Recent studies found that the sigma-1 receptor is a novel ligand-operated ER chaperone that regulates bioenergetics, free radical generation, oxidative stress, unfolded protein response and cytokine signaling. The sigma-1 receptor also regulates morphogenesis of neuronal cells, such as neurite outgrowth, synaptogenesis, and myelination, which can be perturbed by cellular stress. The sigma-1 receptor may thus contribute to a cellular defense system that protects nervous systems against chronic psychological stress. Findings from sigma receptor research imply that not only cell surface monoamine effectors but also intracellular molecules, especially those at the ER, may provide novel therapeutic targets for future drug developments.

  12. Salivary cortisol, heart rate, electrodermal activity and subjective stress responses to the Mannheim Multicomponent Stress Test (MMST).

    PubMed

    Reinhardt, Tatyana; Schmahl, Christian; Wüst, Stefan; Bohus, Martin

    2012-06-30

    The availability of effective laboratory paradigms for inducing psychological stress is an important requirement for experimental stress research. Reliable protocols are scarce, usually laborious and manpower-intensive. In order to develop an economical, easily applicable standardized stress protocol, we have recently tailored the Mannheim Multicomponent Stress Test (MMST). This test has been shown to induce relatively high stress responses without focusing on social-evaluative components. In this study we evaluated changes in electrodermal activity and salivary cortisol in response to the MMST. The MMST simultaneously combines cognitive (mental arithmetic), emotional (affective pictures), acoustic (white noise) and motivational stressors (loss of money). This study comprised two independent experiments. For experiment 1, 80 female subjects were recruited; 30 subjects (15 females) participated in experiment 2. Significant changes in electrodermal activity and salivary cortisol levels in response to MMST exposure were found. Subjective stress and heart rate responses were significantly increased in both experiments. These results indicate that the MMST is an economical stress paradigm which is also applicable in larger cohorts or multicenter studies for investigating stress reactions. As social-evaluative threat is not the main stress component of the MMST, this procedure represents a useful and complementary alternative to other established stress protocols.

  13. Maternal stress and plural breeding with communal care affect development of the endocrine stress response in a wild rodent.

    PubMed

    Bauer, Carolyn M; Hayes, Loren D; Ebensperger, Luis A; Ramírez-Estrada, Juan; León, Cecilia; Davis, Garrett T; Romero, L Michael

    2015-09-01

    Maternal stress can significantly affect offspring fitness. In laboratory rodents, chronically stressed mothers provide poor maternal care, resulting in pups with hyperactive stress responses. These hyperactive stress responses are characterized by high glucocorticoid levels in response to stressors plus poor negative feedback, which can ultimately lead to decreased fitness. In degus (Octodon degus) and other plural breeding rodents that exhibit communal care, however, maternal care from multiple females may buffer the negative impact on pups born to less parental mothers. We used wild, free-living degus to test this hypothesis. After parturition, we manipulated maternal stress by implanting cortisol pellets in 0%, 50-75%, or 100% of adult females within each social group. We then sampled pups for baseline and stress-induced cortisol, negative feedback efficacy, and adrenal sensitivity. From groups where all mothers were implanted with cortisol, pups had lower baseline cortisol levels and male pups additionally had weaker negative feedback compared to 0% or 50-75% implanted groups. Contrary to expectations, stress-induced cortisol did not differ between treatment groups. These data suggest that maternal stress impacts some aspects of the pup stress response, potentially through decreased maternal care, but that presence of unstressed mothers may mitigate some of these effects. Therefore, one benefit of plural breeding with communal care may be to buffer post-natal stress.

  14. The Small RNA GcvB Promotes Mutagenic Break Repair by Opposing the Membrane Stress Response

    PubMed Central

    Barreto, Brittany; Rogers, Elizabeth; Xia, Jun; Frisch, Ryan L.; Richters, Megan; Fitzgerald, Devon M.

    2016-01-01

    ABSTRACT Microbes and human cells possess mechanisms of mutagenesis activated by stress responses. Stress-inducible mutagenesis mechanisms may provide important models for mutagenesis that drives host-pathogen interactions, antibiotic resistance, and possibly much of evolution generally. In Escherichia coli, repair of DNA double-strand breaks is switched to a mutagenic mode, using error-prone DNA polymerases, via the SOS DNA damage and general (σS) stress responses. We investigated small RNA (sRNA) clients of Hfq, an RNA chaperone that promotes mutagenic break repair (MBR), and found that GcvB promotes MBR by allowing a robust σS response, achieved via opposing the membrane stress (σE) response. Cells that lack gcvB were MBR deficient and displayed reduced σS-dependent transcription but not reduced σS protein levels. The defects in MBR and σS-dependent transcription in ΔgcvB cells were alleviated by artificially increasing σS levels, implying that GcvB promotes mutagenesis by allowing a normal σS response. ΔgcvB cells were highly induced for the σE response, and blocking σE response induction restored both mutagenesis and σS-promoted transcription. We suggest that GcvB may promote the σS response and mutagenesis indirectly, by promoting membrane integrity, which keeps σE levels lower. At high levels, σE might outcompete σS for binding RNA polymerase and so reduce the σS response and mutagenesis. The data show the delicate balance of stress response modulation of mutagenesis. IMPORTANCE Mutagenesis mechanisms upregulated by stress responses promote de novo antibiotic resistance and cross-resistance in bacteria, antifungal drug resistance in yeasts, and genome instability in cancer cells under hypoxic stress. This paper describes the role of a small RNA (sRNA) in promoting a stress-inducible-mutagenesis mechanism, mutagenic DNA break repair in Escherichia coli. The roles of many sRNAs in E. coli remain unknown. This study shows that ΔgcvB cells

  15. Mitochondrial functions modulate neuroendocrine, metabolic, inflammatory, and transcriptional responses to acute psychological stress

    PubMed Central

    Picard, Martin; McManus, Meagan J.; Gray, Jason D.; Nasca, Carla; Moffat, Cynthia; Kopinski, Piotr K.; Seifert, Erin L.; McEwen, Bruce S.; Wallace, Douglas C.

    2015-01-01

    The experience of psychological stress triggers neuroendocrine, inflammatory, metabolic, and transcriptional perturbations that ultimately predispose to disease. However, the subcellular determinants of this integrated, multisystemic stress response have not been defined. Central to stress adaptation is cellular energetics, involving mitochondrial energy production and oxidative stress. We therefore hypothesized that abnormal mitochondrial functions would differentially modulate the organism’s multisystemic response to psychological stress. By mutating or deleting mitochondrial genes encoded in the mtDNA [NADH dehydrogenase 6 (ND6) and cytochrome c oxidase subunit I (COI)] or nuclear DNA [adenine nucleotide translocator 1 (ANT1) and nicotinamide nucleotide transhydrogenase (NNT)], we selectively impaired mitochondrial respiratory chain function, energy exchange, and mitochondrial redox balance in mice. The resulting impact on physiological reactivity and recovery from restraint stress were then characterized. We show that mitochondrial dysfunctions altered the hypothalamic–pituitary–adrenal axis, sympathetic adrenal–medullary activation and catecholamine levels, the inflammatory cytokine IL-6, circulating metabolites, and hippocampal gene expression responses to stress. Each mitochondrial defect generated a distinct whole-body stress-response signature. These results demonstrate the role of mitochondrial energetics and redox balance as modulators of key pathophysiological perturbations previously linked to disease. This work establishes mitochondria as stress-response modulators, with implications for understanding the mechanisms of stress pathophysiology and mitochondrial diseases. PMID:26627253

  16. Immune and stress response 'cross-talk' in the Drosophila Malpighian tubule.

    PubMed

    Davies, Shireen-Anne; Overend, Gayle; Sebastian, Sujith; Cundall, Maria; Cabrero, Pablo; Dow, Julian A T; Terhzaz, Selim

    2012-04-01

    The success of insects is in large part due to their ability to survive environmental stress, including heat, cold, and dehydration. Insects are also exposed to infection, osmotic or oxidative stress, and to xenobiotics or toxins. The molecular mechanisms of stress sensing and response have been widely investigated in mammalian cell lines, and the area of stress research is now so vast to be beyond the scope of a single review article. However, the mechanisms by which stress inputs to the organism are sensed and integrated at the tissue and cellular level are less well understood. Increasingly, common molecular events between immune and other stress responses are observed in vivo; and much of this work stems of efforts in insect molecular science and physiology. We describe here the current knowledge in the area of immune and stress signalling and response at the level of the organism, tissue and cell, focussing on a key epithelial tissue in insects, the Malpighian tubule, and drawing together the known pathways that modulate responses to different stress insults. The tubules are critical for insect survival and are increasingly implicated in responses to multiple and distinct stress inputs. Importantly, as tubule function is central to survival, they are potentially key targets for insect control, which will be facilitated by increased understanding of the complexities of stress signalling in the organism.

  17. Rearing conditions have long-term consequences for stress responsiveness in free-living great tits.

    PubMed

    Landys, Mėta M; Goymann, Wolfgang; Slagsvold, Tore

    2011-11-01

    In captivity, the adrenocortical stress response can be permanently altered by events that occur during early life. Free-living animals have rarely been examined in this regard. To examine whether early-life events impact the hypothalamo-pituitary-adrenal (HPA) axis in the natural setting, we evaluated the stress response of free-living interspecifically cross-fostered great tits (Parus major). Cross-fostered birds may show a long-term potentiation of the adrenocortical stress response because species-specific nutritional requirements may not be met in the nest and/or cross-fostered birds may experience psychosocial stress while being raised by heterospecifics. Nevertheless, we hypothesized that in the natural setting, programmed changes in HPA function would be eclipsed by reactive responses to the immediate environment. Thus, we predicted that adult cross-fostered great tits and controls would show no differences in their adrenocortical stress response. Contrary to predictions, we found that stress responsiveness (i.e., the rate of the corticosterone increase associated with capture and handling) was significantly higher in cross-fostered great tits than in controls. Further, stress responsiveness was not significantly different between mature adults and first-year juveniles. Thus, data indicate significant effects of early rearing conditions on adrenocortical reactivity in the natural setting and also suggest that effects of rearing conditions in free-living animals can last into adulthood.

  18. The role of the hypothalamic-pituitary-adrenal axis in neuroendocrine responses to stress

    PubMed Central

    Smith, Sean M.; Vale, Wylie W.

    2006-01-01

    Animals respond to stress by activating a wide array of behavioral and physiological responses that are collectively referred to as the stress response. Corticotropin-releasing factor (CRF) plays a central role in the stress response by regulating the hypothalamic-pituitary-adrenal (HPA) axis. In response to stress, CRF initiates a cascade of events that culminate in the release of glucocorticoids from the adrenal cortex. As a result of the great number of physiological and behavioral effects exerted by glucocorticoids, several mechanisms have evolved to control HPA axis activation and integrate the stress response. Glucocorticoid feedback inhibition plays a prominent role in regulating the magnitude and duration of glucocorticoid release. In addition to glucocorticoid feedback, the HPA axis is regulated at the level of the hypothalamus by a diverse group of afferent projections from limbic, mid-brain, and brain stem nuclei. The stress response is also mediated in part by brain stem noradrenergic neurons, sympathetic andrenornedullary circuits, and parasympathetic systems. In summary, the aim of this review is to discuss the role of the HPA axis in the integration of adaptive responses to stress. We also identify and briefly describe the major neuronal and endocrine systems that contribute to the regulation of the HPA axis and the maintenance of homeostasis in the face of aversive stimuli. PMID:17290797

  19. Eccentric-exercise induced inflammation attenuates the vascular responses to mental stress.

    PubMed

    Paine, Nicola J; Ring, Christopher; Aldred, Sarah; Bosch, Jos A; Wadley, Alex J; Veldhuijzen van Zanten, Jet J C S

    2013-05-01

    Mental stress has been identified as a trigger of myocardial infarction (MI), with inflammation and vascular responses to mental stress independently implicated as contributing factors. This study examined whether inflammation moderates the vascular responses to mental stress. Eighteen healthy male participants completed a stress task under two counter balanced conditions. In the exercise condition, a morning bout of eccentric exercise (12×5 repetitions of unilateral eccentric knee extension at 120% intensity of concentric one repetition maximum) was used to increase levels of inflammatory-responsive cytokines during an afternoon stress session scheduled 6h later. In the control condition, participants sat and relaxed for 45min, 6h prior to the afternoon stress session. Forearm blood flow, calf blood flow (measured in the leg which completed the exercise task), blood pressure, heart rate and cardiac output were assessed at rest and in response to mental stress. As expected, interleukin-6 was higher (p=.02) 6h post exercise, i.e., at the start of the stress session, as compared to the no-exercise control condition. Mental stress increased forearm blood flow, calf blood flow, blood pressure, heart rate, and cardiac output in both conditions (p's<.001). Stress-induced calf blood flow was attenuated in the exercise condition compared to the control condition (p<.05) which was not the case for forearm blood flow. This study found that the inflammatory response to eccentric exercise attenuated the vascular responses to mental stress locally at the site of eccentric exercise-induced inflammation. The observed impairment in vascular responses to stress associated with increased levels of inflammation suggests a mechanism through which inflammation might increase the risk for MI.

  20. Transcriptional analysis of different stress response genes in Escherichia coli strains subjected to sodium chloride and lactic acid stress.

    PubMed

    Peng, Silvio; Stephan, Roger; Hummerjohann, Jörg; Tasara, Taurai

    2014-12-01

    Survival of Escherichia coli in food depends on its ability to adapt against encountered stress typically involving induction of stress response genes. In this study, the transcriptional induction of selected acid (cadA, speF) and salt (kdpA, proP, proW, otsA, betA) stress response genes was investigated among five E. coli strains, including three Shiga toxin-producing strains, exposed to sodium chloride or lactic acid stress. Transcriptional induction upon lactic acid stress exposure was similar in all but one E. coli strain, which lacked the lysine decarboxylase gene cadA. In response to sodium chloride stress exposure, proW and otsA were similarly induced, while significant differences were observed between the E. coli strains in induction of kdpA, proP and betA. The kdpA and betA genes were significantly induced in four and three strains, respectively, whereas one strain did not induce these genes. The proP gene was only induced in two E. coli strains. Interestingly, transcriptional induction differences in response to sodium chloride stress exposure were associated with survival phenotypes observed for the E. coli strains in cheese as the E. coli strain lacking significant induction in three salt stress response genes investigated also survived poorly compared to the other E. coli strains in cheese.

  1. Gene expression patterns and stress response in marine copepods.

    PubMed

    Lauritano, Chiara; Procaccini, Gabriele; Ianora, Adrianna

    2012-05-01

    Aquatic organisms are constantly exposed to both physical (e.g. temperature and salinity variations) and chemical (e.g. endocrine disruptor chemicals, heavy metals, hydrocarbons, diatom toxins, and other toxicants) stressors which they react to by activating a series of defense mechanisms. This paper reviews the literature on the defense systems, including detoxification enzymes and proteins (e.g. glutathione S-transferases, heat shock proteins, superoxide dismutase and catalase), studied in copepods at the molecular level. The data indicate high inter- and intra-species variability in copepod response, depending on the type of stressor tested, the concentration and exposure time, and the enzyme isoform studied. Ongoing -omics approaches will allow the identification of new genes which will give a more comprehensive overview of how copepods respond to specific stressors in laboratory and/or field conditions and the effects of these responses on higher trophic levels.

  2. Cardiovascular Responses to Psychosocial Stress Reflect Motivation State in Adults Born at Extremely Low Birth Weight

    PubMed Central

    Pyhälä, Riikka; Hovi, Petteri; Räikkönen, Katri; Van Lieshout, Ryan J.; Boyle, Michael H.; Saigal, Saroj; Morrison, Katherine M.; Kajantie, Eero; Schmidt, Louis A.

    2015-01-01

    Background. Adults born extremely preterm appear to have more difficulty managing the stresses of early adulthood than their term-born peers. Objective. To examine the effects of being born at extremely low birth weight (ELBW; birth weight < 1000 g) versus at full term on cardiovascular responses to stress. Method. Cardiovascular responses were elicited during administration of a widely used laboratory stressor, the Trier Social Stress Test (TSST). Results. Term-born adults exhibited a larger decrease in total peripheral resistance and larger increase in cardiac output for TSST performance, reflecting greater resilience, than did ELBW adults. Furthermore, in ELBW participants but not controls, cardiovascular responses were correlated with anxiety, suggesting that their responses reflected feelings of stress. Conclusions. Skills-training and practice with relevant stressors may be necessary to increase the personal resources of ELBW participants for managing stress as they transition to adulthood. PMID:27335948

  3. Antagonistic interplay between hypocretin and leptin in the lateral hypothalamus regulates stress responses.

    PubMed

    Bonnavion, Patricia; Jackson, Alexander C; Carter, Matthew E; de Lecea, Luis

    2015-02-19

    The hypothalamic-pituitary-adrenal (HPA) axis functions to coordinate behavioural and physiological responses to stress in a manner that depends on the behavioural state of the organism. However, the mechanisms through which arousal and metabolic states influence the HPA axis are poorly understood. Here using optogenetic approaches in mice, we show that neurons that produce hypocretin (Hcrt)/orexin in the lateral hypothalamic area (LHA) regulate corticosterone release and a variety of behaviours and physiological hallmarks of the stress response. Interestingly, we found that Hcrt neuronal activity and Hcrt-mediated stress responses were inhibited by the satiety hormone leptin, which acts, in part, through a network of leptin-sensitive neurons in the LHA. These data demonstrate how peripheral metabolic signals interact with hypothalamic neurons to coordinate stress and arousal and suggest one mechanism through which hyperarousal or altered metabolic states may be linked with abnormal stress responses.

  4. Antagonistic interplay between hypocretin and leptin in the lateral hypothalamus regulates stress responses

    PubMed Central

    Bonnavion, Patricia; Jackson, Alexander C.; Carter, Matthew E.; de Lecea, Luis

    2015-01-01

    The hypothalamic–pituitary–adrenal (HPA) axis functions to coordinate behavioural and physiological responses to stress in a manner that depends on the behavioural state of the organism. However, the mechanisms through which arousal and metabolic states influence the HPA axis are poorly understood. Here using optogenetic approaches in mice, we show that neurons that produce hypocretin (Hcrt)/orexin in the lateral hypothalamic area (LHA) regulate corticosterone release and a variety of behaviours and physiological hallmarks of the stress response. Interestingly, we found that Hcrt neuronal activity and Hcrt-mediated stress responses were inhibited by the satiety hormone leptin, which acts, in part, through a network of leptin-sensitive neurons in the LHA. These data demonstrate how peripheral metabolic signals interact with hypothalamic neurons to coordinate stress and arousal and suggest one mechanism through which hyperarousal or altered metabolic states may be linked with abnormal stress responses. PMID:25695914

  5. Electric shock causes physiological stress responses in shore crabs, consistent with prediction of pain.

    PubMed

    Elwood, Robert W; Adams, Laura

    2015-11-01

    Animal pain is defined by a series of expectations or criteria, one of which is that there should be a physiological stress response associated with noxious stimuli. While crustacean stress responses have been demonstrated they are typically preceded by escape behaviour and thus the physiological change might be attributed to the behaviour rather than a pain experience. We found higher levels of stress as measured by lactate in shore crabs exposed to brief electric shock than non-shocked controls. However, shocked crabs showed more vigorous behaviour than controls. We then matched crabs with the same level of behaviour and still found that shocked crabs had stronger stress response compared with controls. The finding of the stress response, coupled with previous findings of long-term motivational change and avoidance learning, fulfils the criteria expected of a pain experience.

  6. Expression of Multiple Stress Response Genes by Escherichia Coli Under Modeled Reduced Gravity

    NASA Astrophysics Data System (ADS)

    Vukanti, Raja; Leff, Laura G.

    2012-09-01

    Bacteria, in response to changes in their environment, quickly regulate gene expression; hence, transcriptional profiling has been widely used to characterize bacterial responses to various environmental conditions. In this study, we used clinorotation to grow bacteria under low-sedimentation, -shear, and -turbulence conditions (referred to as modeled reduced gravity, MRG, below) which profoundly impacts bacteria including causing elevated resistance to multiple environmental stresses. To explore potential mechanisms behind the multiple stress resistance response to MRG, we assessed expression levels of E. coli genes, using reverse transcription followed by real-time-PCR, involved in specific stress and general stress responses under MRG and normal gravity (NG) in nutritionally rich and minimal media, and during exponential and stationary phases of growth. In addition, growth rates as well as physico-chemical parameters of culture media were examined. Over-expression of stress response genes (csiD, cstA, katE, otsA, treA) occurred under MRG compared to NG controls, but only during the later stages of growth in rich medium demonstrating that bacterial response to MRG varies with growth-medium and -phase. At stationary phase in rich medium under MRG and NG, E. coli had similar growth rates (based on rRNA-leader abundance) and yields (cell mass and numbers); this coupled, with observations of simultaneous induction of starvation response genes (csiD and cstA) suggests the multiple stress resistance phenotype under MRG could be attributable to microzones of nutrient unavailability around cells. Overall, in rich medium, the response resembled the general stress response (GSR) that E. coli develops during stationary phase of growth. Along these same lines, induction of genes coding for GSR was reversed by improving nutritional conditions under MRG. The reversal of GSR under MRG suggests that the multiple stress response exhibited is not specific to MRG but may result

  7. What Constitutes Effective Coping and Efficient Physiologic Regulation following Psychosocial Stress Depends on Involuntary Stress Responses

    PubMed Central

    Bendezú, Jason J.; Perzow, Sarah E. D.; Wadsworth, Martha E.

    2017-01-01

    This study utilized a random-assignment experimental design to examine the interactive contributions of youth-reported trait involuntary stress responses (ISRs) and effortful coping on physiologic reactivity and recovery patterns in preadolescent boys and girls. Fourth- and fifth-grade child-parent dyads (N=126) participated in this study. Children were exposed to the Trier Social Stress Test (TSST-C) and then to one of two randomly-assigned experimental coping conditions: behavioral distraction and cognitive avoidance. Children’s ISRs were examined as predictors of salivary cortisol and alpha-amylase (sAA) reactivity as well as moderators of the effect of coping condition on cortisol and sAA recovery trajectories. Multi-level modeling analyses did not link ISRs to physiologic reactivity patterning. ISRs and coping condition interacted to predict differential physiologic recovery trajectories. In the distraction condition, children reporting high ISR levels displayed less efficient cortisol and sAA recovery than children reporting low ISR levels. Surprisingly, the opposite was found for children reporting high ISR levels in the avoidance condition. These children displayed more efficient physiologic recovery relative to their high ISR level peers in the distraction condition. Findings suggest that the efficiency of preadolescents’ physiologic recovery following stress may depend on regulatory fit between children’s ISR levels and cues from their coping environment. PMID:27448527

  8. Excitatory influence of the locus coeruleus in hypothalamic-pituitary-adrenocortical axis responses to stress.

    PubMed

    Ziegler, D R; Cass, W A; Herman, J P

    1999-05-01

    The locus coeruleus (LC) is a key brainstem region involved in arousal and is highly responsive to alerting/stressful stimuli, including those that activate the hypothalamic-pituitary-adrenocortical (HPA) axis. It is currently unclear whether the LC exerts any regulatory influence on the HPA axis and, consequently, on neuroendocrine responses to stress. The present studies were designed to test the hypothesis that the LC promotes HPA axis responses to acute and chronic stress. Adult male rats received bilateral (6-hydroxydopamine) lesions of the LC that produced severe cell loss in the LC and 80% depletion of noradrenaline in medial prefrontal cortex. Notably, lesions did not affect dopamine-beta-hydroxylase protein content in the parvocellular paraventricular nucleus (PVN), indicating a lack of collateral damage to other ascending noradrenergic pathways. LC lesions significantly reduced peak adrenocorticotropic hormone (ACTH) and corticosterone responses to 30 min acute restraint stress. However, LC lesions did not significantly attenuate neuroendocrine or other physiological responses to a 4-week chronic variable stress regimen. LC lesions did not substantially affect basal concentrations of plasma corticosterone or corticotropin-releasing hormone mRNA expression in the hypothalamic paraventricular nucleus following chronic stress. We conclude that the LC is a HPA-excitatory brain region, promoting neuroendocrine and physiological responses primarily to acute stress. However, a potential role for the LC in the induction of HPA axis hyperactivity following chronic stress can not be ruled out.

  9. Bordetella bronchiseptica responses to physiological reactive nitrogen and oxygen stresses

    PubMed Central

    Omsland, Anders; Miranda, Katrina M.; Friedman, Richard L.; Boitano, Scott

    2008-01-01

    Bordetella bronchiseptica can establish prolonged airway infection consistent with a highly developed ability to evade mammalian host immune responses. Upon initial interaction with the host upper respiratory tract mucosa, B. bronchiseptica are subjected to antimicrobial reactive nitrogen species (RNS) and reactive oxygen species (ROS), effector molecules of the innate immune system. However, the responses of B. bronchiseptica to redox species at physiologically relevant concentrations (nM-µM) have not been investigated. Using predicted physiological concentrations of nitric oxide (NO), superoxide (O2.−) and hydrogen peroxide (H2O2) on low numbers of colony forming units (CFU) of B. bronchiseptica, all redox active species displayed dose-dependent antimicrobial activity. Susceptibility to individual redox active species was significantly increased upon introduction of a second species at sub-antimicrobial concentrations. An increased bacteriostatic activity of NO was observed relative to H2O2. The understanding of Bordetella responses to physiologically relevant levels of exogenous RNS and ROS will aid in defining the role of endogenous production of these molecules in host innate immunity against Bordetella and other respiratory pathogens. PMID:18462394

  10. Effects of stress, corticosterone, and epinephrine administration on learning in place and response tasks.

    PubMed

    Sadowski, Renee N; Jackson, Gloria R; Wieczorek, Lindsay; Gold, Paul E

    2009-12-14

    These experiments examined the effects of prior stress, corticosterone, or epinephrine on learning in mazes that can be solved efficiently using either place or response strategies. In a repeated stress condition, rats received restraint stress for 6h/day for 21 days, ending 24h before food-motivated maze training. In two single stress conditions, rats received a 1-h episode of restraint stress ending 30 min or 24h prior to training. Single stress ending 30 min prior to training resulted in a significant interaction of stress and learning on the two tasks, with significant enhancement of learning in the response task and non-significant impairment in the place task. Neither acute nor chronic stress significantly altered learning in either task when the stress ended 24h before training. Thus, the anterograde effects of stress on maze learning ended within a single day. Two stress-related hormones, corticosterone and epinephrine, were tested for effects on learning parallel to those of acute stress. When administered 30 min prior to training, a corticosterone dose (40 mg/kg) that enhanced memory on a spontaneous alternation task did not significantly enhance or impair learning in either task. Two doses of epinephrine that modulate memory in other settings were used to test the effects of epinephrine on learning. Pre-training injections of 0.03 mg/kg epinephrine impaired place learning, while 0.1mg/kg epinephrine impaired response learning. The epinephrine results mimicked those seen with acute stress on the place task, but were opposite those seen after acute stress on the response task. Thus, corticosterone does not appear to be a major factor mediating the effects of acute stress on place and response learning and epinephrine is, at most, a partial contributor to these effects.

  11. Impaired neuronal nitric oxide synthase-mediated vasodilator responses to mental stress in essential hypertension.

    PubMed

    Khan, Sitara G; Geer, Amber; Fok, Henry W; Shabeeh, Husain; Brett, Sally E; Shah, Ajay M; Chowienczyk, Philip J

    2015-04-01

    Neuronal NO synthase (nNOS) regulates blood flow in resistance vasculature at rest and during mental stress. To investigate whether nNOS signaling is dysfunctional in essential hypertension, forearm blood flow responses to mental stress were examined in 88 subjects: 48 with essential hypertension (42±14 years; blood pressure, 141±17/85±15 mm Hg; mean±SD) and 40 normotensive controls (38±14 years; 117±13/74±9 mm Hg). A subsample of 34 subjects (17 hypertensive) participated in a single blind 2-phase crossover study, in which placebo or sildenafil 50 mg PO was administered before an intrabrachial artery infusion of the selective nNOS inhibitor S-methyl-l-thiocitrulline (SMTC, 0.05, 0.1, and 0.2 μmol/min) at rest and during mental stress. In a further subsample (n=21) with an impaired blood flow response to mental stress, responses were measured in the presence and absence of the α-adrenergic antagonist phentolamine. The blood flow response to mental stress was impaired in hypertensive compared with normotensive subjects (37±7% versus 70±8% increase over baseline; P<0.001). SMTC blunted responses to mental stress in normotensive but not in hypertensive subjects (reduction of 40±11% versus 3.0±14%, respectively, P=0.01, between groups). Sildenafil reduced the blood flow response to stress in normotensive subjects from 89±14% to 43±14% (P<0.03) but had no significant effect in hypertensive subjects. Phentolamine augmented impaired blood flow responses to mental stress from 39±8% to 67±13% (P<0.02). Essential hypertension is associated with impaired mental stress-induced nNOS-mediated vasodilator responses; this may relate to increased sympathetic outflow in hypertension. nNOS dysfunction may impair vascular homeostasis in essential hypertension and contribute to stress-induced cardiovascular events.

  12. Opioid partial agonist buprenorphine dampens responses to psychosocial stress in humans.

    PubMed

    Bershad, Anya K; Jaffe, Jerome H; Childs, Emma; de Wit, Harriet

    2015-02-01

    Pre-clinical and clinical evidence indicates that opioid drugs have stress-dampening effects. In animal models, opioid analgesics attenuate responses to isolation distress, and in humans, opioids reduce stress related to anticipation of physical pain. The stress-reducing effects of opioid drugs may contribute to their abuse potential. Despite this evidence in laboratory animals, the effects of opioids on responses to psychosocial stress have not been determined in humans. Here we examined the effects of buprenorphine, a μ-opioid partial agonist used to treat opioid dependence and pain, on subjective and physiological responses to a stressful public speaking task in healthy adults. We hypothesized that buprenorphine would reduce subjective and physiological stress responses. Healthy adult volunteers (N=48) were randomly assigned to receive placebo, 0.2mg sublingual buprenorphine, or 0.4mg sublingual buprenorphine in a two-session study with a stressful speaking task (Trier Social Stress Test; TSST) and a non-stressful control task. During the sessions, the participants reported on their mood states, provided subjective appraisals of the task, and measures of salivary cortisol, heart rate, and blood pressure at regular intervals. Stress produced its expected effects, increasing heart rate, blood pressure, salivary cortisol, and subjective ratings of anxiety and negative mood. In line with our hypothesis, both doses of buprenorphine significantly dampened salivary cortisol responses to stress. On self-report ratings, buprenorphine reduced how threatening participants found the tasks. These results suggest that enhanced opioid signaling dampens responses to social stress in humans, as it does in laboratory animals. This stress-dampening effect of buprenorphine may contribute to the non-medical use of opioid drugs.

  13. Sex and stress: Men and women show different cortisol responses to psychological stress induced by the Trier social stress test and the Iowa singing social stress test.

    PubMed

    Reschke-Hernández, Alaine E; Okerstrom, Katrina L; Bowles Edwards, Angela; Tranel, Daniel

    2017-01-02

    Acute psychological stress affects each of us in our daily lives and is increasingly a topic of discussion for its role in mental illness, aging, cognition, and overall health. A better understanding of how such stress affects the body and mind could contribute to the development of more effective clinical interventions and prevention practices. Over the past 3 decades, the Trier Social Stress Test (TSST) has been widely used to induce acute stress in a laboratory setting based on the principles of social evaluative threat, namely, a judged speech-making task. A comparable alternative task may expand options for examining acute stress in a controlled laboratory setting. This study uses a within-subjects design to examine healthy adult participants' (n = 20 men, n = 20 women) subjective stress and salivary cortisol responses to the standard TSST (involving public speaking and math) and the newly created Iowa Singing Social Stress Test (I-SSST). The I-SSST is similar to the TSST but with a new twist: public singing. Results indicated that men and women reported similarly high levels of subjective stress in response to both tasks. However, men and women demonstrated different cortisol responses; men showed a robust response to both tasks, and women displayed a lesser response. These findings are in line with previous literature and further underscore the importance of examining possible sex differences throughout various phases of research, including design, analysis, and interpretation of results. Furthermore, this nascent examination of the I-SSST suggests a possible alternative for inducing stress in the laboratory. © 2016 Wiley Periodicals, Inc.

  14. Regulation of mRNA decay in plant responses to salt and osmotic stress.

    PubMed

    Kawa, Dorota; Testerink, Christa

    2017-04-01

    Plant acclimation to environmental stresses requires fast signaling to initiate changes in developmental and metabolic responses. Regulation of gene expression by transcription factors and protein kinases acting upstream are important elements of responses to salt and drought. Gene expression can be also controlled at the post-transcriptional level. Recent analyses on mutants in mRNA metabolism factors suggest their contribution to stress signaling. Here we highlight the components of mRNA decay pathways that contribute to responses to osmotic and salt stress. We hypothesize that phosphorylation state of proteins involved in mRNA decapping affect their substrate specificity.

  15. Stress response pathways in ameloblasts: implications for amelogenesis and dental fluorosis.

    PubMed

    Sierant, Megan L; Bartlett, John D

    2012-09-01

    Human enamel development of the permanent teeth takes place during childhood and stresses encountered during this period can have lasting effects on the appearance and structural integrity of the enamel. One of the most common examples of this is the development of dental fluorosis after childhood exposure to excess fluoride, an elemental agent used to increase enamel hardness and prevent dental caries. Currently the molecular mechanism responsible for dental fluorosis remains unknown; however, recent work suggests dental fluorosis may be the result of activated stress response pathways in ameloblasts during the development of permanent teeth. Using fluorosis as an example, the role of stress response pathways during enamel maturation is discussed.

  16. Effects of appraisal and coping on the neuroendocrine response to extreme stress.

    PubMed

    Olff, Miranda; Langeland, Willie; Gersons, Berthold P R

    2005-05-01

    Although many people are exposed to extreme stress, only some of them develop psychobiological disturbances that can lead to posttraumatic stress disorder (PTSD) or other posttrauma psychopathology. This paper examines the effects of different types of appraisal and coping to find clues to how individuals differ in their neuroendocrine responses to extreme stress. It proposes a conceptual model for components of the adult response to stressors. Threat appraisal and defensive coping may play crucial roles in determining the neuroendocrine response to trauma with potential mental health consequences, particularly PTSD.

  17. 2012 Gordon Research Conference on Microbial Stress Response, Schedule and Speaker/Poster Program

    SciTech Connect

    Donohue, Timothy J.

    2012-07-20

    The Gordon Research Conference on Microbial Stress Response was held at Mount Holyoke College, South Hadley, Massachusetts, July 15-20, 2012. The Conference was well-attended with 180 participants. The 2012 Microbial Stress Responses Gordon Research Conference will provide a forum for the open reporting of recent discoveries on the diverse mechanisms employed by microbes to respond to stress. Approaches range from analysis at the molecular level (how are signals perceived and transmitted to change gene expression or function) to cellular and microbial community responses. Attached is a copy of the formal schedule and speaker program and the poster program.

  18. Listeria monocytogenes shows temperature-dependent and -independent responses to salt stress, including responses that induce cross-protection against other stresses.

    PubMed

    Bergholz, Teresa M; Bowen, Barbara; Wiedmann, Martin; Boor, Kathryn J

    2012-04-01

    The food-borne pathogen Listeria monocytogenes experiences osmotic stress in many habitats, including foods and the gastrointestinal tract of the host. During transmission, L. monocytogenes is likely to experience osmotic stress at different temperatures and may adapt to osmotic stress in a temperature-dependent manner. To understand the impact of temperature on the responses this pathogen uses to adapt to osmotic stress, we assessed genome-wide changes in the L. monocytogenes H7858 transcriptome during short-term and long-term adaptation to salt stress at 7°C and 37°C. At both temperatures, the short-term response to salt stress included increased transcript levels of sigB and SigB-regulated genes, as well as mrpABCDEFG, encoding a sodium/proton antiporter. This antiporter was found to play a role in adaptation to salt stress at both temperatures; ΔmrpABCDEFG had a significantly longer lag phase than the parent strain in BHI plus 6% NaCl at 7°C and 37°C. The short-term adaptation to salt stress at 7°C included increased transcript levels of two genes encoding carboxypeptidases that modify peptidoglycan. These carboxypeptidases play a role in the short-term adaptation to salt stress only at 7°C, where the deletion mutants had significantly different lag phases than the parent strain. Changes in the transcriptome at both temperatures suggested that exposure to salt stress could provide cross-protection to other stresses, including peroxide stress. Short-term exposure to salt stress significantly increased H(2)O(2) resistance at both temperatures. These results provide information for the development of knowledge-based intervention methods against this pathogen, as well as provide insight into potential mechanisms of cross-protection.

  19. Osmotic stress-induced polyamine oxidation mediates defence responses and reduces stress-enhanced grapevine susceptibility to Botrytis cinerea.

    PubMed

    Hatmi, Saloua; Trotel-Aziz, Patricia; Villaume, Sandra; Couderchet, Michel; Clément, Christophe; Aziz, Aziz

    2014-01-01

    Abiotic factors inducing osmotic stress can influence the plant immune response and resistance to pathogen infections. In this study, the effect of polyethylene glycol (PEG)- and sucrose-induced osmotic stress on polyamine (PA) homeostasis and the basal immune response in grapevine plantlets before and after Botrytis cinerea infection was determined. Pharmacological approaches were also addressed to assess the contribution of osmotic stress-induced PA oxidation to the regulation of defence responses and the susceptibility of grapevine to B. cinerea. Following osmotic stress or pathogen infection, PA homeostasis was linked to enhanced activity of diamine oxidases (CuAO) and PA oxidases (PAO) and the production of 1,3-diaminopropane. These responses paralleled the accumulation of the main stilbenic phytoalexins, resveratrol and ε-viniferin and upregulation of gene transcripts including STS (a stilbene synthase), PR-2 (a β-1,3-glucanase), PR3-4c (acidic chitinase IV), and PR-5 (a thaumatin-like protein), as well as NCED2 involved in abscisic acid biosynthesis. It was also demonstrated that leaves pre-exposed to osmotic stress and later inoculated with B. cinerea showed enhanced PA accumulation and attenuation of CuAO and PAO activities. This was consistent with the impaired production of phytoalexins and transcript levels of defence- and stress-related genes following infection, and the enhanced susceptibility to B. cinerea. Pharmacological experiments revealed that, under osmotic stress conditions, CuAO and PAO were involved in PA homeostasis and in the regulation of defence responses. Specific inhibition of CuAO and PAO in osmotically stressed leaves strongly attenuated the induction of defence responses triggered by B. cinerea infection and enhanced susceptibility to the pathogen. Taken together, this study reveals a contribution of PA catabolism to the resistance state through modulation of immune response in grapevine following osmotic stress and/or after B

  20. ABI3 mediates dehydration stress recovery response in Arabidopsis thaliana by regulating expression of downstream genes.

    PubMed

    Bedi, Sonia; Sengupta, Sourabh; Ray, Anagh; Nag Chaudhuri, Ronita

    2016-09-01

    ABI3, originally discovered as a seed-specific transcription factor is now implicated to act beyond seed physiology, especially during abiotic stress. In non-seed plants, ABI3 is known to act in desiccation stress signaling. Here we show that ABI3 plays a role in dehydration stress response in Arabidopsis. ABI3 gene was upregulated during dehydration stress and its expression was maintained during subsequent stress recovery phases. Comparative gene expression studies in response to dehydration stress and stress recovery were done with genes which had potential ABI3 binding sites in their upstream regulatory regions. Such studies showed that several genes including known seed-specific factors like CRUCIFERIN1, CRUCIFERIN3 and LEA-group of genes like LEA76, LEA6, DEHYDRIN LEA and LEA-LIKE got upregulated in an ABI3-dependent manner, especially during the stress recovery phase. ABI3 got recruited to regions upstream to the transcription start site of these genes during dehydration stress response through direct or indirect DNA binding. Interestingly, ABI3 also binds to its own promoter region during such stress signaling. Nucleosomes covering potential ABI3 binding sites in the upstream sequences of the above-mentioned genes alter positions, and show increased H3 K9 acetylation during stress-induced transcription. ABI3 thus mediates dehydration stress signaling in Arabidopsis through regulation of a group of genes that play a role primarily during stress recovery phase.

  1. A NAP-Family Histone Chaperone Functions in Abiotic Stress Response and Adaptation1[OPEN

    PubMed Central

    Pareek, Ashwani; Singla-Pareek, Sneh Lata

    2016-01-01

    Modulation of gene expression is one of the most significant molecular mechanisms of abiotic stress response in plants. Via altering DNA accessibility, histone chaperones affect the transcriptional competence of genomic loci. However, in contrast to other factors affecting chromatin dynamics, the role of plant histone chaperones in abiotic stress response and adaptation remains elusive. Here, we studied the physiological function of a stress-responsive putative rice (Oryza sativa) histone chaperone of the NAP superfamily: OsNAPL6. We show that OsNAPL6 is a nuclear-localized H3/H4 histone chaperone capable of assembling a nucleosome-like structure. Utilizing overexpression and knockdown approaches, we found a positive correlation between OsNAPL6 expression levels and adaptation to multiple abiotic stresses. Results of comparative transcriptome profiling and promoter-recruitment studies indicate that OsNAPL6 functions during stress response via modulation of expression of various genes involved in diverse functions. For instance, we show that OsNAPL6 is recruited to OsRad51 promoter, activating its expression and leading to more efficient DNA repair and abrogation of programmed cell death under salinity and genotoxic stress conditions. These results suggest that the histone chaperone OsNAPL6 may serve a regulatory role in abiotic stress physiology possibly via modulating nucleosome dynamics at various stress-associated genomic loci. Taken together, our findings establish a hitherto unknown link between histone chaperones and abiotic stress response in plants. PMID:27342307

  2. Glucocorticoids mediate stress-induced impairment of retrieval of stimulus-response memory.

    PubMed

    Atsak, Piray; Guenzel, Friederike M; Kantar-Gok, Deniz; Zalachoras, Ioannis; Yargicoglu, Piraye; Meijer, Onno C; Quirarte, Gina L; Wolf, Oliver T; Schwabe, Lars; Roozendaal, Benno

    2016-05-01

    Acute stress and elevated glucocorticoid hormone levels are well known to impair the retrieval of hippocampus-dependent 'declarative' memory. Recent findings suggest that stress might also impair the retrieval of non-hippocampal memories. In particular, stress shortly before retention testing was shown to impair the retrieval of striatal stimulus-response associations in humans. However, the mechanism underlying this stress-induced retrieval impairment of non-hippocampal stimulus-response memory remains elusive. In the present study, we investigated whether an acute elevation in glucocorticoid levels mediates the impairing effects of stress on retrieval of stimulus-response memory. Male Sprague-Dawley rats were trained on a stimulus-response task in an eight-arm radial maze until they learned to associate a stimulus, i.e., cue, with a food reward in one of the arms. Twenty-four hours after successful acquisition, they received a systemic injection of vehicle, corticosterone (1mg/kg), the corticosterone-synthesis inhibitor metyrapone (35mg/kg) or were left untreated 1h before retention testing. We found that the corticosterone injection impaired the retrieval of stimulus-response memory. We further found that the systemic injection procedure per se was stressful as the vehicle administration also increased plasma corticosterone levels and impaired the retrieval of stimulus-response memory. However, memory retrieval was not impaired when rats were tested 2min after the systemic vehicle injection, before any stress-induced elevation in corticosterone levels had occurred. Moreover, metyrapone treatment blocked the effect of injection stress on both plasma corticosterone levels and memory retrieval impairment, indicating that the endogenous corticosterone response mediates the stress-induced memory retrieval impairment. None of the treatments affected rats' locomotor activity or motivation to search for the food reward within the maze. These findings show that stress

  3. Influence of a Suggestive Placebo Intervention on Psychobiological Responses to Social Stress: A Randomized Controlled Trial.

    PubMed

    Zimmermann-Viehoff, Frank; Steckhan, Nico; Meissner, Karin; Deter, Hans-Christian; Kirschbaum, Clemens

    2016-01-01

    We tested the hypothesis that a suggestive placebo intervention can reduce the subjective and neurobiological stress response to psychosocial stress. Fifty-four healthy male subjects with elevated levels of trait anxiety were randomly assigned in a 4:4:1 fashion to receive either no treatment (n = 24), a placebo pill (n = 24), or a herbal drug (n = 6) before undergoing a stress test. We repeatedly measured psychological variables as well as salivary cortisol, alpha-amylase, and heart rate variability prior to and following the stress test. The stressor increased subjective stress and anxiety, salivary cortisol, and alpha-amylase, and decreased heart rate variability (all P < .001). However, no significant differences between subjects receiving placebo or no treatment were found. Subjects receiving placebo showed increased wakefulness during the stress test compared with no-treatment controls (P < .001). Thus, the suggestive placebo intervention increased alertness, but modulated neither subjective stress and anxiety nor the physiological response to psychosocial stress.

  4. Linking molecular and population stress responses in Daphnia magna exposed to cadmium.

    PubMed

    Connon, Richard; Hooper, Helen L; Sibly, Richard M; Lim, Fei-Ling; Heckmann, Lars-Henrik; Moore, David J; Watanabe, Hajime; Soetaert, Anneleen; Cook, Katie; Maund, Steve J; Hutchinson, Thomas H; Moggs, Jonathan; De Coen, Wim; Iguchi, Taisen; Callaghan, Amanda

    2008-03-15

    DNA microarrays can be used to measure environmental stress responses. If they are to be predictive of environmental impact, we need to determine if altered gene expression translates into negative impacts on individuals and populations. A large cDNA microarray (14000 spots) was created to measure molecular