Evolutionary origin of autonomic regulation of physiological activities in vertebrate phyla

Sequentially bidirectional gastrovascular flows in intricately branched digestive tract of planocerid flatworms

Polyclad flatworms possess an intricately branched digestive system combining features of a gastrovascular cavity as well as a gastrointestinal tract. Nonetheless, the functions of this system remain unconfirmed, due to a lack of effective observation methods. This paper presents a novel staining method to facilitate the analysis of this highly branched digestive system. Video recordings obtained during ingestion revealed sequentially bidirectional gastrovascular flows and a corresponding occurrence of regular contractions. Tissue sections revealed that the contractions can be attributed to a radial arrangement of muscles around the gastrointestinal tract. The highly branched digestive system of the flatworm revealed evidence of bidirectional flow and sequential peristalsis, which may allow for a diet of greater diversity than is possible in animals with only a gastrovascular cavity. The proposed staining technique opens up new avenues for research on the digestive behavior of lower organisms.

Use of Infrared Thermography and Heart Rate Variability to Evaluate Autonomic Activity in Domestic Animals

Most of the responses present in animals when exposed to stressors are mediated by the autonomic nervous system. The sympathetic nervous system, known as the one responsible for the "fight or flight" reaction, triggers cardiovascular changes such as tachycardia or vasomotor alterations to restore homeostasis. Increase in body temperature in stressed animals also activates peripheral compensatory mechanisms such as cutaneous vasodilation to increase heat exchange. Since changes in skin blood flow influence the amount of heat dissipation, infrared thermography is suggested as a tool that can detect said changes. The present review aims to analyze the application of infrared thermography as a method to assess stress-related autonomic activity, and their association with the cardiovascular and heart rate variability in domestic animals.

Heat shock response during the resolution of inflammation and its progressive suppression in chronic-degenerative inflammatory diseases

The heat shock response (HSR) is a crucial biochemical pathway that orchestrates the resolution of inflammation, primarily under proteotoxic stress conditions. This process hinges on the upregulation of heat shock proteins (HSPs) and other chaperones, notably the 70 kDa family of heat shock proteins, under the command of the heat shock transcription factor-1. However, in the context of chronic degenerative disorders characterized by persistent low-grade inflammation (such as insulin resistance, obesity, type 2 diabetes, nonalcoholic fatty liver disease, and cardiovascular diseases) a gradual suppression of the HSR does occur. This work delves into the mechanisms behind this phenomenon. It explores how the Western diet and sedentary lifestyle, culminating in the endoplasmic reticulum stress within adipose tissue cells, trigger a cascade of events. This cascade includes the unfolded protein response and activation of the NOD-like receptor pyrin domain-containing protein-3 inflammasome, leading to the emergence of the senescence-associated secretory phenotype and the propagation of inflammation throughout the body. Notably, the activation of the NOD-like receptor pyrin domain-containing protein-3 inflammasome not only fuels inflammation but also sabotages the HSR by degrading human antigen R, a crucial mRNA-binding protein responsible for maintaining heat shock transcription factor-1 mRNA expression and stability on heat shock gene promoters. This paper underscores the imperative need to comprehend how chronic inflammation stifles the HSR and the clinical significance of evaluating the HSR using cost-effective and accessible tools. Such understanding is pivotal in the development of innovative strategies aimed at the prevention and treatment of these chronic inflammatory ailments, which continue to take a heavy toll on global health and well-being.

Lateralization of autonomic output in response to limb-specific threat

In times of stress or danger, the autonomic nervous system (ANS) signals the fight or flight response. A canonical function of ANS activity is to globally mobilize metabolic resources, preparing the organism to respond to threat. Yet a body of research has demonstrated that, rather than displaying a homogenous pattern across the body, autonomic responses to arousing events - as measured through changes in electrodermal activity (EDA) - can differ between right and left body locations. Surprisingly, an attempt to identify a function of ANS asymmetry consistent with its metabolic role has not been investigated. In the current study, we investigated whether asymmetric autonomic responses could be induced through limb-specific aversive stimulation. Participants were given mild electric stimulation to either the left or right arm while EDA was monitored bilaterally. In a group-level analyses, an ipsilateral EDA response bias was observed, with increased EDA response in the hand adjacent to the stimulation. This effect was observable in ∼50% of individual particpants. These results demonstrate that autonomic output is more complex than canonical interpretations suggest. We suggest that, in stressful situations, autonomic outputs can prepare either the whole-body fight or flight response, or a simply a limb-localized flick, which can effectively neutralize the threat while minimizing global resource consumption. These findings are consistent with recent theories proposing evolutionary leveraging of neural structures organized to mediate sensory responses for processing of cognitive emotional cues.Significance statementThe present study constitutes novel evidence for an autonomic nervous response specific to the side of the body exposed to direct threat. We identify a robust pattern of electrodermal response at the body location that directly receives aversive tactile stimulation. Thus, we demonstrate for the first time in contemporary research that the ANS is capable of location-specific outputs within single effector organs in response to small scale threat. This extends the canonical view of the role of ANS responses in stressful or dangerous stresses - that of provoking a 'fight or flight' response - suggesting a further role of this system: preparation of targeted limb-specific action, i.e., a flick.

Threat induces cardiac and metabolic changes that negatively impact survival in flies

Adjusting to a dynamic environment involves fast changes in the body’s internal state, characterized by coordinated alterations in brain activity and physiological and motor responses. Threat-induced defensive states are a classic case of coordinated adjustment of bodily responses, cardiac regulation being one of the best characterized examples in vertebrates. A great deal is known regarding the neural basis of invertebrate defensive behaviors, mainly in Drosophila melanogaster. However, whether physiological changes accompany these remains unknown. Here, we set out to describe the internal bodily state of fruit flies upon an inescapable threat and found cardiac acceleration during running and deceleration during freezing. In addition, we found that freezing leads to increased cardiac pumping from the abdomen toward the head-thorax, suggesting mobilization of energy resources. Concordantly, threat-triggered freezing reduces sugar levels in the hemolymph and renders flies less resistant to starvation. The cardiac responses observed during freezing were absent during spontaneous immobility, underscoring the active nature of freezing response. Finally, we show that baseline cardiac activity predicts the amount of freezing upon threat. This work reveals a remarkable similarity with the cardiac responses of vertebrates, suggesting an evolutionarily convergent defensive state in flies. Our findings are at odds with the widespread view that cardiac deceleration while freezing has first evolved in vertebrates and that it is energy sparing. Investigating the physiological changes coupled to defensive behaviors in the fruit fly has revealed that freezing is costly yet accompanied by cardiac deceleration and points to heart activity as a key modulator of defensive behaviors.

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Flies show tight coupling between defensive behaviors and cardiac activity

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Flies bias cardiac pumping toward the head and thorax during defensive behaviors

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After prolonged freezing, sugar levels and resistance to starvation are decreased

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Cardiac reversal rate and rate variability are predictive of freezing intensity

Development of a Self Report Stress Scale Using Item Response Theory-I: Item Selection, Formation of Factor Structure and Examination of Its Psychometric Properties

INTRODUCTION

Due to the absence of Turkish psychometric devices assessing stress, in the present study it was aimed to develop a stress scale, and examine its basic psychometric properties.

METHODS

Current study included two processes, formation of item pool and examination of psychometric properties of the selected items through three studies. In the first study, 611 individuals aged between 18 and 77 responded to 130 selected items. In the second study, 2223 individuals aged between 18 and 68 responded to 80 items. In the third study, 1969 individuals aged between 18 and 79 responded to the final form of 36 items. Further, in study 3 for criterion related validity 163 individuals completed the Coopersmith Self-Esteem Inventory, 113 individuals completed the Beck Anxiety Inventory, 104 individuals completed the Hospital Anxiety and Depression Scale, 107 individuals completed the Beck Depression Inventory, and 265 individuals completed the Perceived Stress Scale. Moreover, in the investigation of test-retest reliability, 119 individuals took the final form of the test after 2 weeks, and 111 individuals took the final form of the test after 3 weeks.

RESULTS

In the first study, out of 130 items, 54 that showed item-total score correlations below 0.30 were excluded from the scale. Fifty-seven items were preserved exactly, and 19 items' sentence structures were changed. Furthermore, by adding 4 new items, 80 were prepared for the second study. In the second study, two factors structure namely "Physiological Reactions/Strain" and "Psychological/Cognitive Appraisals" sub-dimensions were identified, and 36 items were selected via Item Response Theory representing these sub-dimensions. In study 3, exploratory factor analysis provided strong support for our hypothesized two factors structure. Confirmatory factor analysis indicated hypothesized model had a better fit to the data. Internal consistency coefficients were 0.94 for the entire scale, 0.90 for Physiological Reactions/Strain sub-dimension, and 0.91 for Psychological/Cognitive Appraisals sub-dimension. Correlation coefficients between the entire scale and other criterion scales ranged from 0.22 to 0.63. Test-retest correlation coefficients between the first administration of the scale, and the administrations at two and three week intervals were 0.88.

CONCLUSION

Results showed that the scale has basic psychometric requirements provided that the scale will be supported by validity studies.

Hypnosis Treatment of Gastrointestinal Disorders: A Comprehensive Review of the Empirical Evidence

Hypnotherapy has been investigated for 30 years as a treatment for gastrointestinal (GI) disorders. There are presently 35 studies in the published empirical literature, including 17 randomized controlled trials (RCTs) that have assessed clinical outcomes of such treatment. This body of research is reviewed comprehensively in this article. Twenty-four of the studies have tested hypnotherapy for adult irritable bowel syndrome (IBS) and 5 have focused on IBS or abdominal pain in children. All IBS hypnotherapy studies have reported significant improvement in gastrointestinal symptoms, and 7 out of 10 RCTs in adults and all 3 RCTs in pediatric patient samples found superior outcomes for hypnosis compared to control groups. Collectively this body of research shows unequivocally that for both adults and children with IBS, hypnosis treatment is highly efficacious in reducing bowel symptoms and can offer lasting and substantial symptom relief for a large proportion of patients who do not respond adequately to usual medical treatment approaches. For other GI disorders the evidence is more limited, but preliminary indications of therapeutic potential can be seen in the single randomized controlled trials published to date on hypnotherapy for functional dyspepsia, functional chest pain, and ulcerative colitis. Further controlled hypnotherapy trials in those three disorders should be a high priority. The mechanisms underlying the impact of hypnosis on GI problems are still unclear, but findings from a number of studies suggest that they involve both modulation of gut functioning and changes in the brain's handling of sensory signals from the GI tract.

New evidence on an old question: is the "fight or flight" stage present in the cardiac and respiratory regulation of decapod crustaceans?

The ability to stay alert to subtle changes in the environment and to freeze, fight or flight in the presence of predators requires integrating sensory information as well as triggering motor output to target tissues, both of which are associated with the autonomic nervous system. These reactions, which are commonly related to vertebrates, are the fundamental physiological responses that allow an animal to survive danger. The circulatory activity in vertebrates changes in opposite phases. The stage where circulatory activity is high is termed the "fight or flight stage", while the stage where circulatory activity slows down is termed the "rest and digest stage". It may be assumed that highly evolved invertebrates possess a comparable response system as they also require rapid cardiovascular and respiratory regulation to be primed when necessary. However, in invertebrates, the body plan may have developed such a system very differently. Since this topic is insufficiently studied, it is necessary to extend studies for a comparative analysis. In the present review, we use our own experimental results obtained in the crab Neohelice granulata and both older and newer findings obtained by other authors in decapod crustaceans as well as in other invertebrates, to compare the pattern of change in circulatory activity, especially in the "fight or flight" stage. We conclude that the main features of neuroautonomic regulation of the cardiac function were already present early in evolution, at least in highly evolved invertebrates, although conspicuous differences are also evident.

The cardiac response of the crab Chasmagnathus granulatus as an index of sensory perception

When an animal's observable behavior remains unaltered, one can be misled in determining whether it is able to sense an environmental cue. By measuring an index of the internal state, additional information about perception may be obtained. We studied the cardiac response of the crab Chasmagnathus to different stimulus modalities: a light pulse, an air puff, virtual looming stimuli and a real visual danger stimulus. The first two did not trigger observable behavior, but the last two elicited a clear escape response. We examined the changes in heart rate upon sensory stimulation. Cardiac response and escape response latencies were also measured and compared during looming stimuli presentation. The cardiac parameters analyzed revealed significant changes (cardio-inhibitory responses) to all the stimuli investigated. We found a clear correlation between escape and cardiac response latencies to different looming stimuli. This study proved useful to examine the perceptual capacity independently of behavior. In addition, the correlation found between escape and cardiac responses support previous results which showed that in the face of impending danger the crab triggers several coordinated defensive reactions. The ability to escape predation or to be alerted to subtle changes in the environment in relation to autonomic control is associated with the complex ability to integrate sensory information as well as motor output to target tissues. This ;fear, fight or flight' response gives support to the idea of an autonomic-like reflexive control in crustaceans.