Effect of psychological stress on gastric motility assessed by electrical bio-impedance

Standard Adult Gastric Emptying Scintigraphy Criteria Is Applicable for Partial Meal Ingestion

BACKGROUND/AIMS

Gastric emptying scintigraphy is commonly performed to assess for dysmotility. A standardized meal with associated threshold criteria was established in 2000 to enable robust interpretation. However, no guidance is available to interpret results when patients do not ingest the entire meal. The purpose of this study is to determine the continued appropriateness of the threshold criteria in contemporary clinical practice and its relevance for partially ingested meals.

METHODS

This retrospective study analyzed patients (n = 1365 total) who underwent solid-phase gastric emptying scintigraphy at an academic medical center. Patients were stratified based on their completion of the standard meal. Patients were further stratified into normal and delayed gastric emptying cohorts based on the current criteria. Percent gastric retention values at 1, 2, 3, and 4 h were compared.

RESULTS

Median (95% upper reference) normal gastric retention values for the complete standard meal were 64% (87%) at 1 h, 25% (60%) at 2 h, 13% (54%) at 3 h and 4% (9%) at 4 h. Consumption of at least 50% of the standard meal yielded similar retention; 53% (86%) at 1 h, 19% (58%) at 2 h, 6% (29%) at 3 h and 3% (10%) at 4 h. There was no significant age- or gender-specific differences using the current criteria, and no differences were observed based on diabetic status. Retention values matched well with the current criteria and validated with data-driven clustering.

CONCLUSION

Adult normative standards for gastric emptying scintigraphy are appropriate for differentiating normal and delayed populations and can be applied to partial meals with at least 50% completion.

Physical Activity Reduction and the Worsening of Gastrointestinal Health Status during the Second COVID-19 Home Confinement in Southern Italy

Due to the COVID-19 pandemic, in December 2020, the Italian government established a second home confinement during the Christmas holidays. These restrictions offered the opportunity to utilize a well-defined model for observing the consequences of lifestyle changes of healthy individuals. This study aimed at estimating in healthy subjects from Southern Italy the physical activity (PA), the presence and the severity of gastrointestinal (GI) symptoms, and the association between the possible worsening of GI health status and the PA levels. An adapted version of the International PA Questionnaire-short form (IPAQ-SF) and the Gastrointestinal Symptom Rating Scale (GSRS) were proposed through Google’s online survey platform in three different periods via WhatsApp^TM to 499 healthy subjects (62% females) from Apulia (25%), Calabria (37%), and Campania (38%). Our results showed statistically significant changes during the home confinement: reduced energy expenditure (EE) among overweight subjects (−239.82, 95%CI −405.74; −73.89) or those who had high GSRS total score (−1079.54, 95%CI −2027.43; −131.66). An increase in GSRS total score was observed in overweight subjects, reaching statistical significance in those from Campania. Our study supports the importance of PA to reduce health risks, including those related to the possible onset of GI tract diseases.

Anxiety and Gastrointestinal Symptoms Related to COVID-19 during Italian Lockdown

The first case of infection by SARS-CoV-2 (i.e., COVID-19) was officially recorded by the Italian National Health Service on 21 February 2020. Respiratory tract manifestations are the most common symptoms, such as gastrointestinal symptoms (GISs) like nausea or sickness, diarrhea, and anorexia, and psychological effects may be reported in affected individuals. However, similar symptoms may be observed in healthy people as a consequence of an anxiety state. Methods: We analyzed GISs and anxiety state during the COVID-19 lockdown period; from 9 March 2020 to 4 May 2020. A web-based survey consisting of 131 items was administered to 354 students affiliated with the School of Medicine of the University “Magna Graecia” of Catanzaro; Italy. A set of statistical analyses was performed to analyze the relationships among the answers to assess a correlation between the topics of interest. Results: The statistical analysis showed that 54.0% of interviewed reported at least one GISs, 36.16% of which reported a positive history for familial GISs (FGISs). The 354 subjects included in our cohort may be stratified as follows: 25.99% GISs and FGISs, 27.97% GISs and no-FGISs, 10.17% no-GISs and FGISs, 35.87% no-GISs and no-FGISs. Results indicated an anxiety state for 48.9% of respondents, of which 64.74% also presented GISs. In addition, considered dietary habits, we detect the increased consumption of hypercaloric food, sweetened drinks, and alcoholic beverages. Conclusions: The increase of GISs during the lockdown period in a population of medical students, may be correlated to both dietary habits and anxiety state due to a concern for one’s health.

Repeated Gastric Motility Measurement Affects Gastric Motility and Epigastric Symptom Sensation

Background: Gastric motility is an important determinant of gastric emptying, epigastric symptom generation, and intolerance to food. Motility is classically assessed directly using manometry or an intragastric balloon. These diagnostic methods are perceived as stressful and invasive, which, by itself might influence the readout of these assessments. Our hypothesis was that with repeated exposure to an invasive motility test the outcome would be different.

Methods: Gastric motility was assessed with a custom-made orogastric balloon catheter in 10 healthy subjects naive to intubation. A motility index ranging from 0 (no motility) to 1 (maximum motility) was calculated in the fasted state for 3.5 h. Symptoms were surveyed with visual analog scales of 100 mm. Results are presented as median (interquartile range).

Results: Motility index during visit 1 [0.40 (0.37–0.59)] was lower compared to visit 2 [0.50 (0.45–0.66); not significant] and 3 [0.63 (0.50–0.71); p = 0.016]. Nausea and pain scores were significantly higher during visit 1 (35 (2.8–126) and 103 (88–125) mm, respectively) compared with visit 3 [1 (2.8–26) mm (p = 0.016) and 75 (30–100) mm (p = 0.008), respectively]. No adverse events were observed.

Conclusions: Repeated exposure to an invasive method to assess motility resulted in more vigorous motility and lower symptom scores. Caution is warranted when interpreting functional assessments, as prior exposure to invasive tests might confound the obtained results through habituation.

Exogenous Orexin-A Microinjected Into Central Nucleus of the Amygdala Modulates Feeding and Gastric Motility in Rats

Orexin-A is a circulating neuropeptide and neurotransmitter that regulates food intake and gastric motility. The central nucleus of the amygdala (CeA), which regulates feeding behavior and gastric function, expresses the orexin-1 receptor. The aim of this study was to evaluate the effects of microinjection of exogenous orexin-A into the CeA, on food intake and gastric motility, and to explore the mechanisms of these effects. Normal chow and high fat food (HFF) intake were measured, gastric motility and gastric emptying were evaluated, extracellular single unit firing was recorded, and c-fos expression was determined. The results showed that microinjection of orexin-A into the CeA resulted in increased HFF intake but did not affect normal chow intake. This effect was blocked by an orexin-1 receptor antagonist-SB-334867 and was partially blocked by a dopamine D1 receptor antagonist-SCH-23390. Gastric motility and gastric emptying were enhanced by orexin-A, and the former effect was abolished by subdiaphragmatic vagotomy. The firing frequency of gastric distention-related neurons was regulated by orexin-A via the orexin-1 receptor. Furthermore, c-fos expression was increased in the ventral tegmental area (VTA) and the nucleus accumbens (NAc), the lateral hypothalamus (LHA), and the dorsal motor nucleus of the vagus (DMV) in response to microinjection of orexin-A into the CeA. These findings showed that orexin-A regulated palatable food intake and gastric motility via the CeA. The LHA, the VTA, and the NAc may participate in palatable food intake and the CeA-DMV-vagus-stomach pathway may be involved in regulating gastric motility through the regulation of neuronal activity in the CeA.

Nod-like receptors are critical for gut-brain axis signalling in mice

KEY POINTS

•Nucleotide binding oligomerization domain (Nod)-like receptors regulate cognition, anxiety and hypothalamic-pituitary-adrenal axis activation. •Nod-like receptors regulate central and peripheral serotonergic biology. •Nod-like receptors are important for maintenance of gastrointestinal physiology. •Intestinal epithelial cell expression of Nod1 receptors regulate behaviour.

ABSTRACT

Gut-brain axis signalling is critical for maintaining health and homeostasis. Stressful life events can impact gut-brain signalling, leading to altered mood, cognition and intestinal dysfunction. In the present study, we identified nucleotide binding oligomerization domain (Nod)-like receptors (NLR), Nod1 and Nod2, as novel regulators for gut-brain signalling. NLR are innate immune pattern recognition receptors expressed in the gut and brain, and are important in the regulation of gastrointestinal physiology. We found that mice deficient in both Nod1 and Nod2 (NodDKO) demonstrate signs of stress-induced anxiety, cognitive impairment and depression in the context of a hyperactive hypothalamic-pituitary-adrenal axis. These deficits were coupled with impairments in the serotonergic pathway in the brain, decreased hippocampal cell proliferation and immature neurons, as well as reduced neural activation. In addition, NodDKO mice had increased gastrointestinal permeability and altered serotonin signalling in the gut following exposure to acute stress. Administration of the selective serotonin reuptake inhibitor, fluoxetine, abrogated behavioural impairments and restored serotonin signalling. We also identified that intestinal epithelial cell-specific deletion of Nod1 (VilCre⁺ Nod1^f/f ), but not Nod2, increased susceptibility to stress-induced anxiety-like behaviour and cognitive impairment following exposure to stress. Together, these data suggest that intestinal epithelial NLR are novel modulators of gut-brain communication and may serve as potential novel therapeutic targets for the treatment of gut-brain disorders.

Gastric responses to acute psychological stress in climacteric women: a pilot study

OBJECTIVE

Women exhibit reduced ovarian sex hormones during the menopausal period that result in well-known physical and psychological symptoms. However, symptoms related to gastric motility (GM) have not been thoroughly investigated. We hypothesized that stress response gastric motility (SRGM) is lower in postmenopausal (PM) and perimenopausal (PERIM) women than in premenopausal (PREM) women. Estrogenic decline leads to neuroendocrine changes in different areas of the brain. These changes can result in hypothalamic vasomotor symptoms, disorders in eating behaviours, and altered blood pressure, in addition to psychological disorders such as stress, anxiety, depression, and irritability related to alterations in the limbic system.

METHODS

In this pilot study, 55 PREM, PERIM, and PM women were clinically evaluated using the Nowack stress profile (SP) and State-Trait Anxiety Inventory (STAI). GM was assessed via electrical bioimpedance using two psychological stress tests (Stroop and Raven tests).

RESULTS

Basal SP and STAI-anxiety test scores were similar among the three groups of women (P > 0.05). PERIM women had lower GM in the basal state (P < 0.05) than did other women. PREM and PM women had significantly decreased GM during the stress tests (P < 0.05). However, PERIM did not exhibit GM changes during stress tests (P > 0.05).

CONCLUSION

Changes in sex hormones during PERIM may affect GM and SRGM.

Relationship between job stress and functional dyspepsia in display manufacturing sector workers: a cross-sectional study

Background

Job stress has been reported as a risk factor of psychological changes, which have been shown to be related to gastrointestinal diseases and symptoms such as functional dyspepsia. However, few studies have assessed the relationship between job stress and functional dyspepsia. Therefore, we investigated the relationship between job stress and functional dyspepsia in South Korea.

Methods

This study was conducted between May 23 and July 6, 2016 and included 901 workers in the display manufacturing sector. Subjects completed self-reported questionnaires, regarding Korean Occupational Stress Scale (KOSS), functional dyspepsia, Insomnia Severity Index-K, and health-related behaviors and job characteristics. Subjects were divided into functional dyspepsia-positive and -negative groups based on the Rome III criteria. The KOSS high-risk group was defined as subjects with KOSS score above the 75 percentile of KOSS reference value. Multiple logistic regression analysis was performed to investigate the association between job stress and functional dyspepsia.

Results

In women, the risk of functional dyspepsia was significantly higher in the high-risk groups of the following KOSS subcategories in unadjusted model: job demand (OR 3.282, 95% CI 1.181–9.126), and occupational climate (OR 2.665, 95% CI 1.041–6.823). Even in adjusted model, the risk was significantly higher in the high-risk groups of the following KOSS subcategories: job demand (OR 3.123, 95% CI 1.036–9.416) and occupational climate (OR 3.304, 95% CI 1.198–9.115). In men, the risk of functional dyspepsia was not significant in all KOSS subcategories.

Conclusions

This study showed that job demand and occupational climates were associated with functional dyspepsia in female display manufacturing sector workers. Therefore, both clinical and mental health approaches should be used in the management of functional dyspepsia in women.

Elevated faecal ovotransferrin concentrations are indicative for intestinal barrier failure in broiler chickens

Intestinal health is critically important for the welfare and performance of poultry. Enteric diseases that cause gut barrier failure result in high economic losses. Up till now there is no reliable faecal marker to measure gut barrier failure under field conditions. Therefore, the aim of the present study was to identify a faecal protein marker for diminished intestinal barrier function due to enteric diseases in broilers. To assess this, experimental necrotic enteritis and coccidiosis in broilers were used as models for gut barrier failure. Ovotransferrin was identified as a marker for gut barrier failure using a proteomics approach on samples from chickens with necrotic enteritis. These results were confirmed via ELISA on samples derived from both necrotic enteritis and coccidiosis trials, where faecal ovotransferrin levels were significantly correlated with the severity of gut barrier failure caused by either coccidiosis or necrotic enteritis. This indicates that faecal ovotransferrin quantification may represent a valuable tool to measure gut barrier failure caused by enteric pathogens.

Psychological effects of Helicobacter pylori-associated atrophic gastritis in patients under 50 years: A cross-sectional study

BACKGROUND

While gastrointestinal function is known to be closely related to psychological status, the influence of Helicobacter pylori-associated atrophic gastritis is currently unknown. We aimed to determine whether atrophic gastritis status or H. pylori infection is associated with psychological distress or depressed mood.

MATERIALS AND METHODS

We performed a cross-sectional, observational study involving 975 Japanese individuals (503 females; mean age, 44 ± 8 years) who underwent a health checkup. Psychological distress was defined as a Kessler-6 Scale score ≥13 and depressive mood as a Center for Epidemiological Studies Depression Scale score ≥ 16. The odds ratios with 95% confidence intervals assessing the risk of psychological distress or depressive mood associated with H. pylori infection (H. pylori-specific immunoglobulin G levels >10 U/mL) and atrophic gastritis status (pepsinogen I levels < 70 μg/L and pepsinogen I/II ratio < 3) were calculated using multiple logistic analysis adjusting for several covariates.

RESULTS

Individuals with atrophic gastritis had a significantly higher risk of experiencing psychological distress, with younger females (<50 years) displaying the highest risk for psychological distress and depressive mood regardless of H. pylori infection status. Among females aged <50 years, H. pylori-seropositive participants with atrophic gastritis (HP+AG+) showed the highest risk of psychological distress (OR, 16.4; 95% CI, 3.45-94.9) and depression (OR, 2.86; 95% CI, 1.31-6.05), using HP-AG- status as the reference.

CONCLUSIONS

Our findings support the results of previous animal studies regarding the psychological response to gastritis in humans. Further studies are needed to elucidate whether H. pylori eradication provides psychological benefits.

Rethinking the role of alpha toxin in Clostridium perfringens-associated enteric diseases: a review on bovine necro-haemorrhagic enteritis

Bovine necro-haemorrhagic enteritis is an economically important disease caused by Clostridium perfringens type A strains. The disease mainly affects calves under intensive rearing conditions and is characterized by sudden death associated with small intestinal haemorrhage, necrosis and mucosal neutrophil infiltration. The common assumption that, when causing intestinal disease, C. perfringens relies upon specific, plasmid-encoded toxins, was recently challenged by the finding that alpha toxin, which is produced by all C. perfringens strains, is essential for necro-haemorrhagic enteritis. In addition to alpha toxin, other C. perfringens toxins and/or enzymes might contribute to the pathogenesis of necro-haemorrhagic enteritis. These additional virulence factors might contribute to breakdown of the protective mucus layer during initial stage of pathogenesis, after which alpha toxin, either or not in synergy with other toxins such as perfringolysin O, can act on the mucosal tissue. Furthermore, alpha toxin alone does not cause intestinal necrosis, indicating that other virulence factors might be needed to cause the extensive tissue necrosis observed in necro-haemorrhagic enteritis. This review summarizes recent research that has increased our understanding of the pathogenesis of bovine necro-haemorrhagic enteritis and provides information that is indispensable for the development of novel control strategies, including vaccines.

Anxiety and physiological responses to the Trier Social Stress Test for Children in adolescents with cyclic vomiting syndrome

This study compared anxiety and physiological responses during the Trier Social Stress Test for Children (TSST-C) in adolescents. 38 subjects (26 females) were enrolled: 11 cyclic vomiting syndrome (CVS), 11 anxiety, and 16 controls. Salivary cortisol, α-amylase and heart rate variability (HRV) were assessed during the TSST-C. Anxiety was measured by the Screen for Childhood Anxiety Related Emotional Disorders (SCARED), Anxiety Disorders Interview Schedule, and State-Trait Anxiety Inventory for Children (STAI-C). 11 anxiety and 7 CVS subjects had ≥1 anxiety disorder. 82% in the anxiety and CVS groups met criteria for an anxiety disorder on the SCARED. Combining groups, cortisol increased from baseline to recovery during the TSST-C (p=0.0004) and the stressor to recovery (p=0.005). α-amylase did not differ during the TSST-C for the total sample, but increased for anxiety compared to controls from baseline to recovery (p=0.01). HRV decreased during the stressor (p=0.0001) and increased at recovery (p=0.004). No associations were found between biomarkers and trait anxiety. Associations were found between baseline HRV and pre-test state anxiety (r=-0.406, p=0.012) and between recovery HRV and post-test state anxiety (r=-0.501, p=0.002) for the total sample. Anxiety is prevalent in CVS warranting screening. HRV may serve as a biomarker for evaluating stress as a potential trigger for CVS episodes. State but not trait anxiety was associated with changes in HRV, suggesting acute anxiety may be more relevant in linking stress and CVS episodes.

Effects of electrical stimulation at different locations in the central nucleus of amygdala on gastric motility and spike activity

The aim of the study was to determine the effects of electrical stimulation of different locations in the central nucleus of amygdala (CNA) on gastric motility and spike activity in dorsal vagal complex. Gastric motility index (GMI) and firing rate (FR) of dorsal vagal complex neurons were measured in adult Wistar rats respectively. Neuronal spikes in dorsal vagal complex (DVC) were recorded extracellularly with single-barrel glass microelectrodes. Each type of responses elicited by electrical stimulation in medial (CEM) and lateral (CEL) subdivisions of CNA were recorded, respectively. GMI was significantly increased after stimulation of CEM (p<0.01), and significantly decreased in response to CEL stimulation (p<0.01). After stimulation of CEM, FR in medial nucleus of the solitary tract (mNST) decreased by 31.6 % (p<0.01) and that in dorsal motor nucleus of the vagus (DMNV) increased by 27.1 % (p<0.01). On the contrary, FR in mNST increased (p<0.01) and that in DMNV decreased in response to CEL stimulation (p<0.05). In conclusions, our findings indicated that different loci of CNA may mediate differential effects on gastric activity via changes in the firing of brainstem neurons controlling gut activity.

Evaluation of gastric emptying in diabetic gastropathy by an ultrasonic whole stomach cylinder method

In order to explore the accuracy of ultrasonic whole stomach cylinder measurement (UWSCM) in the evaluation of gastric emptying, we measured the gastric emptying times (ET) at 25% (T1), 50% (T2) and 75% (T3) of healthy subjects and patients with diabetic gastropathy by UWSCM and scintigraphy. The ET of patients were compared with their clinical symptom scores. We found that the ET measured by UWSCM showed no significant difference with scintigraphy (p > 0.05). The correlation between them was good, and the correlation coefficient of T3 reached 0.744 (p < 0.05). All emptying times in the diabetic patients were longer than those in the healthy subjects (p < 0.05). The T3 in the diabetic group measured by UWSCM had the best correlation with the symptom index (r = 0.469, p < 0.05). We conclude that ET measured by UWSCM is accurate and T3 combining the symptoms index provides an accurate clinical basis for gastropathy.

The psyche and gastric functions

Although the idea that gastric problems are in some way related to mental activity dates back to the beginning of the last century, until now it has received scant attention by physiologists, general practitioners and gastroenterologists. The major breakthrough in understanding the interactions between the central nervous system and the gut was the discovery of the enteric nervous system (ENS) in the 19th century. ENS (also called 'little brain') plays a crucial role in the regulation of the physiological gut functions. Furthermore, the identification of corticotropin-releasing factor (CRF) and the development of specific CRF receptor antagonists have permitted to characterize the neurochemical basis of the stress response. The neurobiological response to stress in mammals involves three key mechanisms: (1) stress is perceived and processed by higher brain centers; (2) the brain mounts a neuroendocrine response by way of the hypothalamic-pituitary-adrenal axis (HPA) and the autonomic nervous system (ANS), and (3) the brain triggers feedback mechanisms by HPA and ANS stimulation to restore homeostasis. Various stressors such as anger, fear, painful stimuli, as well as life or social learning experiences affect both the individual's physiologic and gastric function, revealing a two-way interaction between brain and stomach. There is overwhelming experimental and clinical evidence that stress influences gastric function, thereby outlining the pathogenesis of gastric diseases such as functional dyspepsia, gastroesophageal reflux disease and peptic ulcer disease. A better understanding of the role of pathological stressors in the modulation of disease activity may have important pathogenetic and therapeutic implications.

Effects of occupational stress on the gastrointestinal tract

The aim of this review is to provide a general overview of the relationship between occupational stress and gastrointestinal alterations. The International Labour Organization suggests occupational health includes psychological aspects to achieve mental well-being. However, the definition of health risks for an occupation includes biological, chemical, physical and ergonomic factors but does not address psychological stress or other affective disorders. Nevertheless, multiple investigations have studied occupational stress and its physiological consequences, focusing on specific risk groups and occupations considered stressful. Among the physiological effects of stress, gastrointestinal tract (GIT) alterations are highly prevalent. The relationship between occupational stress and GIT diseases is evident in everyday clinical practice; however, the usual strategy is to attack the effects but not the root of the problem. That is, in clinics, occupational stress is recognized as a source of GIT problems, but employers do not ascribe it enough importance as a risk factor, in general, and for gastrointestinal health, in particular. The identification, stratification, measurement and evaluation of stress and its associated corrective strategies, particularly for occupational stress, are important topics to address in the near future to establish the basis for considering stress as an important risk factor in occupational health.

Biological and psychological markers of stress in humans: focus on the Trier Social Stress Test

Validated biological and psychological markers of acute stress in humans are an important tool in translational research. The Trier Social Stress Test (TSST), involving public interview and mental arithmetic performance, is among the most popular methods of inducing acute stress in experimental settings, and reliably increases hypothalamic-pituitary-adrenal axis activation. However, although much research has focused on HPA axis activity, the TSST also affects the sympathetic-adrenal-medullary system, the immune system, cardiovascular outputs, gastric function and cognition. We critically assess the utility of different biological and psychological markers, with guidance for future research, and discuss factors which can moderate TSST effects. We outline the effects of the TSST in stress-related disorders, and if these responses can be abrogated by pharmacological and psychological treatments. Modified TSST protocols are discussed, and the TSST is compared to alternative methods of inducing acute stress. Our analysis suggests that multiple readouts are necessary to derive maximum information; this strategy will enhance our understanding of the psychobiology of stress and provide the means to assess novel therapeutic agents.