Evaluation of salivary α-amylase and immunoglobulin A responses after endurance exercise in adolescent males and females with similar aerobic fitness.

The objective of this study was to clarify whether there are sex-specific differences in salivary α-amylase and immunoglobulin A responses following acute endurance exercise in adolescent males and females with equivalent cardiorespiratory fitness levels. Twenty-six aerobically trained adolescent males and females with similar training status were enrolled in this study. Each individual executed a 1-h prolonged cycling exercise corresponding to a constant power output at 65% of peak oxygen uptake. Unstimulated whole salivary samples were taken with the passive drooling method at the 10-min period before and after exercise for the determination of salivary responses [α-amylase, immunoglobulin A, total protein and flow rate]. Salivary α-amylase activity, immunoglobulin A concentration and total protein concentration were significantly augmented immediately after acute endurance exercise. Regarding sex differences, only the salivary flow rate was significantly lower in females than in males. The findings of the present study imply that adolescent males and females appear to have similar salivary responses after acute endurance exercise, as represented by salivary α-amylase activity and immunoglobulin A concentration in connection with total protein concentration and salivary flow rate, when they are matched for peak oxygen uptake relative to fat-free body mass.

Genetic and environmental influences on alpha amylase stress reactivity and shared genetic covariation with cortisol.

Salivary alpha amylase (sAA) is a common measure of stress reactivity, primarily reflecting sympathetic nervous system activity. Salivary cortisol is also a reliable, frequently used biomarker of stress and reflects the hypothalamic-pituitary-adrenal (HPA) axis response. This study examined heritability across varying metrics of sAA in response to a social evaluative stressor, the Trier Social Stress Test (TSST). The goal of this study was to estimate genetic and environmental influences on measurements of sAA stress reactivity. Moreover, we evaluated the shared genetic covariation between sAA and cortisol. Participants included twins aged 15-20 years (54% female). We measured alpha amylase and cortisol reactivity to the TSST via serial salivary cortisol samples collected pre- and post-TSST. Modest to moderate heritability estimates (11-64%) were observed across measures purported to capture alpha amylase stress reactivity (peak, area under the curve, baseline-to-peak change). Findings also indicate that sAA baseline and peak are primarily influenced by a shared genetic factor. There was no evidence of shared genetic influences between sAA and cortisol. These findings suggest the genetic control of the HPA and Sympathetic Adreno-Medullar axis are genetically independent of one another despite both playing a role in response to stressors.

Development of enzyme-inorganic hybrid nanoflower-modified electrodes and a smartphone-controlled electrochemical analyzer for point-of-care testing of salivary amylase in saliva.

Quantitation of salivary alpha-amylase (sAA) plays a significant role in not only theoretical studies but also clinical practice. This study reports a quantitative point-of-care testing (POCT) system for sAA quantitation anywhere, anytime and by anyone, which consists of customized electrodes and a smartphone-controlled electrochemical analyzer. Organic-inorganic hybrid nanoflowers (NFs) encapsulating α-glucosidase (AG) and glucose dehydrogenase (GDH) have been synthesized and modified onto screen-printed electrodes (SPCEs) to fabricate the customized electrodes. The SPCEs integrated with the smartphone-controlled electrochemical analyzer exhibit good analytical performance for sAA with a low detection limit of 5.02 U mL-1 and a wide dynamic range of 100-2000 U mL-1 using chronoamperometry. The reported POCT system has been successfully demonstrated for quantitation of sAA in clinical saliva samples, and the quantitation results correlated well with those of the Bernfeld method which is extensively used in clinics. More importantly, this study reveals the great potential of sAA as an early warning indicator of abnormal glucose metabolism in obese individuals. Considering the non-invasive saliva sampling process as well as the easy-to-use and cost-effectiveness features of this quantitative POCT system, quantitation of salivary sAA at home by laypersons might become an appealing choice for obese individuals to monitor their glucose metabolism status anytime.

Dental caries prevalence and severity positively associate with AMY1 gene copy number.

OBJECTIVE: To establish the possible relation between total caries (TC) and caries severity (CS) with the AMY1 gene copy number (AMY1GCN). MATERIALS AND METHODS: This was an observational, cross-sectional, population-based, and association study with 303 participants. Each participant underwent a complete anamnesis and stomatological check-up, and peripheral blood was obtained to extract gDNA. TC and CS were determined as the number of caries at the dental exploration and the number of dental surfaces affected by caries, respectively, and AMY1GCN was determined by qPCR. RESULTS: We found an elevated caries prevalence (92.7%); TC and CS were 8 ± 10 and 10 ± 13 (median ± IR). There were higher TC and CS in those participants with AMY1GCN above the mean value (0.02 and 0.01 p values, respectively). A positive correlation between TC and CS with AMY1GCN (0.11 and 0.125 r values, 0.03 and 0.01 p values, respectively) was found, in addition to an association between TC and CS with AMY1GCN (1.5 and 1.6 OR values, 0.48 and 0.26 p values, respectively). CONCLUSION: TC and CS were positively related to the AMY1GCN. CLINICAL RELEVANCE: Dental caries has a high prevalence and a multifactorial etiology and has been related to a genetic component. Indeed, the salivary enzyme alpha-amylase could play a significant role in caries susceptibility, considering that its codifying gene (AMY1) can show variation in its gene copy number. This can be considered an important factor for the development of caries at a genetic level.

Assessment of the human response to acute mental stress-An overview and a multimodal study.

Numerous vital signs are reported in association with stress response assessment, but their application varies widely. This work provides an overview over methods for stress induction and strain assessment, and presents a multimodal experimental study to identify the most important vital signs for effective assessment of the response to acute mental stress. We induced acute mental stress in 65 healthy participants with the Mannheim Multicomponent Stress Test and acquired self-assessment measures (Likert scale, Self-Assessment Manikin), salivary α-amylase and cortisol concentrations as well as 60 vital signs from biosignals, such as heart rate variability parameters, QT variability parameters, skin conductance level, and breath rate. By means of statistical testing and a self-optimizing logistic regression, we identified the most important biosignal vital signs. Fifteen biosignal vital signs related to ventricular repolarization variability, blood pressure, skin conductance, and respiration showed significant results. The logistic regression converged with QT variability index, left ventricular work index, earlobe pulse arrival time, skin conductance level, rise time and number of skin conductance responses, breath rate, and breath rate variability (F1 = 0.82). Self-assessment measures indicated successful stress induction. α-amylase and cortisol showed effect sizes of -0.78 and 0.55, respectively. In summary, the hypothalamic-pituitary-adrenocortical axis and sympathetic nervous system were successfully activated. Our findings facilitate a coherent and integrative understanding of the assessment of the stress response and help to align applications and future research concerning acute mental stress.

Biological stress responses to multitasking and work interruptions: A randomized controlled trial.

In the course of digitalization, new stressors are emerging. In modern working and living environments, two ubiquitous, technology-mediated stressors are multitasking demands and work interruptions. However, biological stress response patterns to multitasking and work interruptions have been sparsely investigated so far. We thus aimed to comprehensively assess biological stress response patterns to both stressors and, additionally, test whether responses differ between digital and partially non-digital settings. A controlled experimental set-up was established and humans' biological markers of the Sympathetic Nervous System (SNS), the hypothalamic-pituitary adrenal (HPA) axis, and the immune system were assessed. N = 186 healthy participants (mean age: 23.2 ± 4.3 years, 74.7% female, body mass-index: 22.3 ± 3.1 kg/m2) took part in this pre-registered study. Each participant was randomly assigned to one of 6 experimental conditions (1 digital single-task, 3 dual-tasks [2 parallel tasks and 1 interruption], 1 multitasking, and 1 passive, control condition). Each one of the dual-tasking as well as the multitasking conditions included a non-digital sub-task, i.e., performing a task in presence of an examiner. All other conditions involved digital tasks only. Salivary alpha-amylase (sAA) levels as a marker for SNS reactivity significantly changed in work interruptions, parallel dual-tasking, and multitasking conditions. No changes were found for control conditions. Furthermore, no significant changes over time and no differences between the conditions were identified for three biological markers: cortisol as marker for HPA axis activity as well as for two immune system markers (secretory Immunoglobulin-A, C-reactive protein). A time course similar to sAA was found for perceived stress: with increases during task execution and decreases afterwards in multitasking and parallel dual-tasking. Yet, it did not change for the work interruption, passive control, and single-tasking condition. Overall, our findings show that dual- and multitasking are perceived as stressful and are associated with an activation of the SNS, but not with responses of HPA axis or immune system. This was consistent for digital as well as partially digital task demands. Our findings will also inform future research into the differential stress effects of digital and non-digital tasks to advance our understanding of biological stress response-patterns to multitasking and work interruptions. Therefore, our findings are highly relevant for understanding the long-term biological health effects of stress in modern (digitalized) environments.

Associations of SLC6A4 methylation with salivary cortisol, salivary alpha-amylase, and subjective stress in everyday life.

Dysregulations of the hypothalamic-pituitary-adrenal (HPA) and sympatho-adrenal medullary (SAM) axis are associated with mental and somatic illness. However, there is lack of knowledge regarding the molecular mechanisms underlying these effects. Epigenetic states in the serotonin transporter gene (SLC6A4) were shown to be associated with stress in various forms. We hypothesized that levels of DNA methylation (DNAm) of SLC6A4 would be associated with altered SAM- and HPA regulation in daily life. N = 74 healthy persons participated in the study. An ecological momentary assessment (EMA) approach was used to assess indicators of stress in daily life. Each day included six concurrent assessments of saliva, to quantify cortisol (sCort; HPA axis) and alpha-amylase (sAA; SAM axis), and to assess self-reports on subjective stress. To assess SLC6A4 DNAm, peripheral blood was drawn and analyzed via bisulfite pyrosequencing. All data were assessed in two waves three months apart, each including two days of EMA and the assessment of SLC6A4 DNAm. Data were analyzed using multilevel models. On the between-person level, higher average levels of SLC6A4 DNAm were associated with higher average levels of sAA, but not with average levels of sCort. On the within-person level, higher levels of SLC6A4 DNAm were associated with lower levels of sAA and sCort. There were no associations of subjective stress with SLC6A4 DNAm. The results help to clarify the association between environmental stress and stress axes regulation, pointing towards an important role of differential within- and between-person effects of SLC6A4 DNAm, which might shape this association.

[From genotype to phenotype: amylase gene in childhood obesity]. / Del genotipo al fenotipo: gen de la amilasa en obesidad infantil.

Worldwide, Mexico is one of the countries with the highest rate of obesity, which is a condition considered the main risk factor for type 2 diabetes. Among the mechanisms that predispose to obesity, the interaction between food intake and genetic components has been little explored. Recently we evidenced a significant association between the copy number (CN) of AMY1A and AMY2A genes, the enzymatic activity of salivary and pancreatic amylase, and the frequency of childhood obesity in Mexico, a particular population due to the high consumption of starch in the diet and the high prevalence of obesity in children and adults. This review aims to find a better understanding of the role of amylase in obesity through a description of the evolution of the CN of its genes, the association of its enzymatic activity with obesity, and the effect of its interaction with starch intake on Mexican children. In addition, it denotes the importance of the experimental perspectives of further investigation regarding the mechanism by which amylase could regulate the abundance of oligosaccharide-fermenting bacteria and producers of short-chain fatty acids and/or branched-chain amino acids that could contribute to the alteration of the physiological processes associated with intestinal inflammation and metabolic deregulation that predispose to the development of obesity.

A nivel mundial, México es uno de los países con la tasa más alta de obesidad, un padecimiento considerado como el principal factor de riesgo de diabetes tipo 2. Dentro de los mecanismos que predisponen a la obesidad, la interacción entre la ingesta alimentaria y el componente genético ha sido poco explorada. Recientemente evidenciamos la asociación del número de copias (NC) de los genes AMY1A y AMY2A, y la actividad enzimática de amilasa salival y pancreática con la frecuencia de obesidad infantil en México, una población que se caracteriza por presentar alto consumo de almidón en la dieta y alta prevalencia de obesidad. La presente revisión busca conseguir un mejor entendimiento del papel de la amilasa en la obesidad por medio de una descripción de la evolución del NC de sus genes, la asociación de su actividad enzimática con la obesidad y el efecto de su interacción con la ingesta de almidón en niños mexicanos. Además, refiere las perspectivas experimentales que permitirían profundizar en la investigación del mecanismo por el cual la amilasa podría regular la abundancia de bacterias fermentadoras de oligosacáridos y productoras de ácidos grasos de cadena corta o aminoácidos de cadena ramificada que podrían contribuir con la alteración de los procesos fisiológicos asociados con la inflamación intestinal y la desregulación metabólica que predispone al desarrollo de obesidad.

Starch intake, amylase gene copy number variation, plasma proteins, and risk of cardiovascular disease and mortality.

BACKGROUND: Salivary amylase, encoded by the AMY1 gene, initiate the digestion of starch. Whether starch intake or AMY1 copy number is related to disease risk is currently rather unknown. The aim was to investigate the association between starch intake and AMY1 copy number and risk of cardiovascular disease (CVD) and mortality and whether there is an interaction. In addition, we aim to identify CVD-related plasma proteins associated with starch intake and AMY1 copy number. METHODS: This prospective cohort study used data from 21,268 participants from the Malmö Diet and Cancer Study. Dietary data were collected through a modified diet history method and incident CVD and mortality were ascertained through registers. AMY1 gene copy number was determined by droplet digital polymerase chain reaction, a risk score of 10 genetic variants in AMY1 was measured, and a total of 88 selected CVD-related proteins were measured. Cox proportional hazards regression was used to analyze the associations of starch intake and AMY1 copy number with disease risk. Linear regression was used to identify plasma proteins associated with starch intake and AMY1 copy number. RESULTS: Over a median of 23 years' follow-up, 4443 individuals developed CVD event and 8125 died. After adjusting for potential confounders, a U-shape association between starch intake and risk of CVD (P-nonlinearity = 0.001) and all-cause mortality (P-nonlinearity = 0.03) was observed. No significant association was found between AMY1 copy number and risk of CVD and mortality, and there were no interactions between starch intake and AMY1 copy number (P interaction > 0.23). Among the 88 plasma proteins, adrenomedullin, interleukin-1 receptor antagonist protein, fatty acid-binding protein, leptin, and C-C motif chemokine 20 were associated with starch intake after adjusting for multiple testing. CONCLUSIONS: In this large prospective study among Swedish adults, a U-shaped association between starch intake and risk of CVD and all-cause mortality was found. Several plasma proteins were identified which might provide information on potential pathways for such association. AMY1 copy number was not associated with CVD risk or any of the plasma proteins, and there was no interaction between starch intake and AMY1 copy number on disease risk.

Effects of sodium bicarbonate bath on the quality of sleep: An assessor-blinded, randomized, controlled, pilot clinical trial.

BACKGROUND: Sleep is fundamental to a healthy life, and sleep disorders are an important health issue in healthcare. Whole-body warm water bathing is a non-pharmacological, safe (non-invasive), and widely used method for comforting. Here, we explored the feasibility and preliminary effectiveness of sodium bicarbonate bath (SBB) on sleep quality. METHODS: Healthy adults without sleep disturbances were randomly assigned to shower baths (SHB), tap-water baths (TWB, placebo tablets), or SBB. All participants took a bath (shower, tap-water, or SBB) once a day for 10 min, after dinner, for 7 days. Sleepscan-derived sleep parameters, including total sleep time (TST), symptom questionnaires, and salivary α-amylase concentration were evaluated as outcome measures. RESULTS: Forty participants were enrolled (14, 13, and 13 in SHB, TWB, and SBB groups, respectively) and 38 participants completed the trial (13, 12, and 13, respectively). The recruitment, adherence, and completion rates were 90.9% (40/44), 95.0% (38/40), and 95.0% (38/40), respectively. The SBB group showed a significant increase (12.35 [mean]±10.07 [standard deviation] min) in the mean TST at 1-week post-intervention (p = 0.0041) than the SHB (-1.81 ± 14.58 min; p = 0.0231) and TWB (4.54 ± 10.97 min; p = 0.0377) groups. The TST scores at 1-week post-intervention, sleep onset latency, wake after sleep onset, and sleep efficiency were significantly different between the groups. Sleep satisfaction by questionnaire was significantly improved with intervention in the SBB group than that in the SHB and TWB groups. Salivary α-amylase levels significantly improved in the SBB and TWB groups than in the SHB group, with the change being greater in the SBB group. CONCLUSIONS: SBB for 7 days had positive effects that improved sleep quality of adults. Further studies are needed to examine the efficacy and safety of SBB for prolonged usage in people diagnosed with insomnia, using objective sleep measurements, and to investigate potential sleep-enhancing mechanisms of action.

Post-awakening salivary alpha-amylase as modulator of treatment response in patients with burnout and major depression.

Around 50% of patients with major depression do not respond to standard first-line treatments, such as psychotherapy and pharmacotherapy. At the same time, a subgroup exhibits altered functioning of stress-responsive bodily systems, such as the central locus coeruleus/sympathetic nervous system and the hypothalamic-pituitary-adrenal (HPA) axis. Given that these systems impact arousal and cognition, it is possible that this subgroup contributes to the high rates of non-responders. Our aim was to investigate whether sympathetic and HPA axis activity modulate treatment outcomes in patients with stress-related major depression. A total of N = 74 inpatients (median age: 50, 62% male) with signs of burnout who fulfilled diagnostic criteria for major depression were recruited. Saliva samples were collected at awakening as well as 30 and 45 min later. Alpha-amylase activity and cortisol concentrations were determined before patients underwent evidence-based multimodal treatment. Non-responders were defined as patients exhibiting a <50% decrease in depression on the Beck Depression Inventory. Non-responders had significantly higher post-awakening alpha-amylase activity than responders (p = .025). In addition, alpha-amylase activity increased significantly over the course of treatment (p = .004), irrespective of responder status. Post-awakening cortisol was neither a predictor nor an indicator of treatment response. If future research confirms alpha-amylase activity as a modulator of treatment response, this may indicate a subgroup of patients with major depression which may benefit from augmentative treatments, such as heart rate variability biofeedback and/or cognitive interventions targeting high arousal.

Salivary α-amylase activity and flow rate explain differences in temporal flavor perception in a chewing gum matrix comprising starch-limonene inclusion complexes.

Starch-guest inclusion complexes (ICs) are a novel, clean-label flavor encapsulation system with the potential to improve stability of aroma volatiles. While amylase has been shown to modulate guest release in vitro, release by sensory perception has not been evaluated. Here, Temporal Check-All-That-Apply (TCATA) and CATA were used to compare flavor perception of starch-limonene ICs to uncomplexed limonene, and the differences in perception were explored as a function of participant salivary α-amylase activity (sAA) and salivary flow rate (sFR). High sFR levels decreased limonene perception while high sAA increased limonene perception, highlighting the potential influence of these physiological factors on flavor perception of foods. Temporal flavor perception of a chewing gum containing starch-limonene ICs and a second chewing gum containing uncomplexed limonene and corn starch (CTL) was evaluated by 99 untrained consumers who assessed taste, texture, and aroma attributes over 17 min by TCATA and CATA. In addition, participants were segmented into three clusters based on their sAA and sFR, and cluster TCATA curves for each sample and attribute were statistically compared. Overall, participants rated Citrus, Sour and Bitter (p < 0.05) significantly higher for the IC sample and rated Sweet higher for the CTL. For Citrus, Sour, and Bitter, significant differences were observed between the three clusters for the IC chewing gum, while the CTL gum showed no significant differences for these three attributes. We demonstrate that flavor perception of starch-guest ICs varies with participants' salivary α-amylase activity and flow rate. Additionally, TCATA and CATA were found to be well suited to characterize flavor release systems over a long period of time as multiple flavor percepts can be simultaneously tracked.

Physiological stress reactivity in pediatric cancer survivors treated with chemotherapy.

Children who experience early life stress demonstrate changes to their stress responses, which may modulate long-term health. Childhood cancer presents significant stress during diagnosis, treatment, and survivorship. We hypothesized that children who have completed chemotherapy treatment for ALL will demonstrate altered hormone patterns in response to a stressor compared with healthy controls. Twelve pediatric ALL survivors and 12 healthy controls completed the Trier Social Stress Test. Salivary samples, heart rate, and self-report ratings of stress were collected at baseline, pretest, and posttest. Between group comparison showed baseline (interleukin [IL]-8) was significantly higher in the survivor group versus controls (survivors: 89.9, 40.1-544.9 pg ml-1 ; controls: 30.7, 5.6-241.9 pg ml-1 , p = .001) as was peak (IL-8) (survivors: 147.1, 71.6-1177.6 pg ml-1 ; controls: 75.5, 28.6-698.6 pg ml-1 ). Peak salivary alpha-amylase (sAA) concentration was significantly lower in the survivor group (survivors: 69.3, 19.4-195.5 U ml-1 ; controls: 91.2, 27.7-213.7 U ml-1 ; p = .04). Repeated measures ANOVA revealed significant main effects for time on cortisol (F(2.35, 50.81)  = 5.9, p < .01), sAA (F(1.56, 33.17)  = 6.6, p < .01), stress ratings (F(3.42, 88.14)  = 53.4, p < .001), and heart rate (F(8, 83)  = 16.8, p < .05). Significant main effects for group were observed for IL-8 (F(1, 23)  = 8.2, p < .01) and tumor necrosis factor-α (F(1, 23)  = 6.8, p < .05). Significant interaction effects for group × time were found for sAA (F(5, 106)  = 2.8, p < .05). Our results indicate that childhood ALL survivors have similar responses to stress as healthy controls, but lower sympatho-adrenal-medullary reactivity. Therefore, altered stress regulation may present a pathway modulating long-term health in this population.

The independent association between salivary alpha-amylase activity and arterial stiffness in Japanese men and women: the Toon Health Study.

Psychological stress is considered to be a potential contributor in the development of arterial stiffness. However, an independent association between arterial stiffness and biological markers of stress has not yet been established. We examined the independent association between salivary alpha-amylase (sAA) activity and arterial stiffness, not mediated by cardiometabolic disease associated with arterial stiffness, in a sample of healthy Japanese men and women. Participants (992 in total, 296 men and 696 women aged 30-79 years) had neither previous cardiovascular events or stroke, nor coexisting hypertension, diabetes, or dyslipidemia. Arterial stiffness was measured by the cardio-ankle vascular index (CAVI), and increased CAVI was defined as a CAVI value of 9 or higher. A saliva sample was collected in the morning and sAA was measured with a commercial assay kit. Higher sAA activity was positively associated with greater arterial stiffness particularly among women (ß = 0.070; 95% CI = 0.014-0.126; p = 0.01), and not across all participants (ß = 0.042; 95% CI = -0.005-0.089; p = 0.08) and in men (ß = -0.005; 95% CI = -0.097-0.087; p = 0.91). The association was strongest in the group of women aged 60 years and older (ß = 0.121; 95% CI = 0.018-0.224; p = 0.02). Although the association between sAA and increased CAVI (CAVI ≥ 9) was not significant in all and sex subgroups, odds ratios (OR) for CAVI ≥ 7 were significantly high in all participants (OR = 1.25; 95% CI = 1.03-1.53) and women (OR = 1.43; 95% CI = 1.12-1.82). Elevation of sAA was associated with an increase in arterial stiffness, particularly for women aged 60 years or older.

Coordination of autonomic and endocrine stress responses to the Trier Social Stress Test in adolescence.

Dysregulations in autonomic and endocrine stress responses are linked to the emergence of psychopathology in adolescence. However, most studies fail to consider the interplay between these systems giving rise to conflicting findings and a gap in understanding adolescent stress response regulation. A multisystem framework-investigation of parasympathetic (PNS), sympathetic (SNS), and hypothalamic pituitary adrenal (HPA) axis components and their coordination-is necessary to understand individual differences in stress response coordination which contribute to stress vulnerabilities. As the first investigation to comprehensively evaluate these three systems in adolescence, the current study employed the Trier Social Stress Test in 72 typically developing adolescents (mean age = 13) to address how PNS, SNS, and HPA stress responses are coordinated in adolescence. Hypotheses tested key predictions of the Adaptive Calibration Model (ACM) of stress response coordination. PNS and SNS responses were assessed via heart rate variability (HRV) and salivary alpha amylase (sAA) respectively. HPA responses were indexed by salivary cortisol. Analyses utilized piecewise growth curve modeling to investigate these aims. Supporting the ACM theory, there was significant hierarchical coordination between the systems such that those with low HRV had higher sAA and cortisol reactivity and those with high HRV had low-to-moderate sAA and cortisol responsivity. Our novel results reveal the necessity of studying multisystem dynamics in an integrative fashion to uncover the true mechanisms of stress response and regulation during development. Additionally, our findings support the existence of characteristic stress response profiles as predicted by the ACM model.

Elevated levels of salivary α- amylase activity in saliva associated with reduced odds of obesity in adult Qatari citizens: A cross-sectional study.

The relationship between salivary α-amylase activity (ssAAa) and the risk of metabolic disorders remains equivocal. We aimed to assess this relationship in adults from Qatar, where obesity and type 2 diabetes are highly prevalent. We cross-sectionally quantified ssAAa in saliva and estimated AMY1 CN from whole-genome sequencing data from 1499 participants. Linear regression was used to assess the relationship between ssAAa and adiposity and glycemic markers. Logistic regression was used to examine the association between ssAAa and occurrence of obesity or diabetes. The mean and median ssAAa were significantly lower in obese individuals. There were significant inverse associations between ssAAa and BMI, and fat mass. We detected a marked effect of ssAAa on reduced odds of obesity after adjusting for age and sex, glucose, LDL, HLD, total cholesterol, and systolic and diastolic blood pressure (OR per ssAAa unit 0.998 [95% CI 0.996-0.999], p = 0.005), with ssAAa ranging between 6.8 and 422U/mL. The obesity odds were significantly lower in the upper half of the ssAAa distributional (OR 0.58 [95% CI 0.42-0.76], p<0.001) and lower in the top versus the bottom decile of the ssAAa distribution (OR 0.46 [95% CI 0.23-0.92], p = 0.03). Our findings suggest a potential beneficial relationship between high sAAa in saliva and low odds of obesity in Qatari adults.

The contribution of gastric digestion of starch to the glycaemic index of breads with different composition or structure.

Breads of higher density exhibit lower glycaemic index (GI) both in vivo and in vitro, a phenomenon generally attributed to a slower intestinal starch digestion. The aim of this work was to gain a better understanding of the relationship between bread density, oral and gastric digestion, and GI. Three breads were studied: industrial-style and traditional-style French baguettes (similar composition, different densities), and whole-wheat baguette. In vitro GI predictions confirmed that, for an identical composition, higher bread density was associated with a lower GI. Subsequent oro-gastric digestions, using the dynamic system DIDGI®, showed extensive starch digestion at the gastric stage by salivary α-amylase, in line with recently published data. They further showed that higher bread density led to a lower hydrolysis rate. The concurrence of these results with those of in vivo studies, suggests a mediating role for gastric digestion in the relationship between bread density and GI, possibly via the repercussions on the starch proportion that remains to be hydrolysed in the small intestine. This study therefore adds to the scientific knowledge of the importance of salivary α-amylase to starch digestion, and draws special attention to the possible role of the gastric phase in determining the GI.

Adult attachment style and salivary alpha-amylase and emotional responses to a psychosocial stressor in women with eating disorders.

BACKGROUND: The fine-tuning of the endogenous stress response system, which includes the hypothalamus-pituitary-adrenal axis and the sympathetic nervous system (SNS), is influenced by early attachment relationships. A higher prevalence of insecure attachment has been detected in people with eating disorders (EDs). Thus, we investigated the emotional and the SNS reactivity to the Trier Social Stress Test (TSST) in women with EDs in relation to their attachment profiles. METHODS: Fifty women with EDs and 20 healthy women participated into an experimental study. Attachment was evaluated by Experience in Close Relationship questionnaire. Salivary α-amylase (sAA) levels were measured to assess the SNS reactivity to TSST while the emotional response was measured by the STAI state scale. RESULTS: Compared to women with EDs and low attachment anxiety and healthy controls, women with EDs and high attachment anxiety showed lower TSST-induced sAA production without difference in anxiety scores. Women with EDs and high attachment avoidance showed similar sAA response to TSST but higher levels of anxiety scores compared to those with low attachment avoidance and healthy controls. CONCLUSIONS: Our findings corroborate the idea that adult attachment may be associated with variability in emotional and biological responses to a psychosocial stressor in women with EDs.

No evidence for a modulating effect of continuous transcutaneous auricular vagus nerve stimulation on markers of noradrenergic activity.

Although transcutaneous auricular vagus nerve stimulation (taVNS) is thought to increase central noradrenergic activity, findings supporting such mechanism are scarce and inconsistent. This study aimed to investigate whether taVNS modulates indirect markers of phasic and tonic noradrenergic activity. Sixty-six healthy participants performed a novelty auditory oddball task twice on separate days: once while receiving taVNS (left cymba concha), once during sham (left earlobe) stimulation. To maximize potential effects, the stimulation was delivered continuously (frequency: 25 Hz; width: 250 µs) at an intensity individually calibrated to the maximal level below pain threshold. The stimulation was administered 10 min before the oddball task and maintained throughout the session. Event-related pupil dilation (ERPD) to target stimuli and pre-stimulus baseline pupil size were assessed during the oddball task as markers of phasic and tonic noradrenergic activity, respectively. Prior to and at the end of stimulation, tonic pupil size at rest, cortisol, and salivary alpha-amylase were assessed as markers of tonic noradrenergic activity. Finally, we explored the effect of taVNS on cardiac vagal activity, respiratory rate, and salivary flow rate. Results showed a greater ERPD to both target and novelty compared to standard stimuli in the oddball task. In contrast to our hypotheses, taVNS did not impact any of the tested markers. Our findings strongly suggest that continuous stimulation of the cymba concha with the tested stimulation parameters is ineffective to increase noradrenergic activity via a vagal pathway.

Verdinexor, a Selective Inhibitor of Nuclear Exportin 1, Inhibits the Proliferation and Migration of Esophageal Cancer via XPO1/c-Myc/FOSL1 Axis.

Esophageal carcinoma (EC) ranks sixth among cancers in mortality worldwide and effective drugs to reduce EC incidence and mortality are lacking. To explore potential anti-esophageal cancer drugs, we conducted drug screening and discovered that verdinexor, a selective inhibitor of nuclear exportin 1 (XPO1/CRM1), has anti-esophageal cancer effects both in vivo and in vitro. However, the mechanism and role of verdinexor in esophageal cancer remain unknown. In the present study, we observed that verdinexor inhibited the proliferation and migration of EC cells in vitro and suppressed tumor growth in vivo. Additionally, we found that verdinexor induced cleavage of PARP and downregulated XPO1, c-Myc, and FOSL1 expression. RNA-sequence analysis and protein-protein interaction (PPI) analysis revealed that verdinexor regulated the XPO1/c-Myc/FOSL1 axis. The results of immunoprecipitation and proximity ligation assays confirmed that verdinexor disrupted the interaction between XPO1 and c-Myc. Overexpression of c-Myc rescued the inhibition of cell proliferation and cell migration caused by verdinexor. Overexpressed FOSL1 restored the inhibited migration by verdinexor. Taken together, verdinexor inhibited cell proliferation and migration of esophageal cancer via XPO1/c-Myc/FOSL1 axis. Our findings provide a new option for the development of anti-esophageal cancer drugs.