Search results for "alpha-Amylase"
showing 10 items of 43 documents
Salivary protein profiles and sensitivity to the bitter taste of caffeine.
2011
WOS: 000298381900008; International audience; The interindividual variation in the sensitivity to bitterness is attributed in part to genetic polymorphism at the taste receptor level, but other factors, such as saliva composition, might be involved. In order to investigate this, 2 groups of subjects (hyposensitive, hypersensitive) were selected from 29 healthy male volunteers based on their detection thresholds for caffeine, and their salivary proteome composition was compared. Abundance of 26 of the 255 spots detected on saliva electrophoretic patterns was significantly different between hypo- and hypersensitive subjects. Saliva of hypersensitive subjects contained higher levels of amylase…
Autonomic markers associated with generalized social phobia symptoms: heart rate variability and salivary alpha-amylase.
2016
The study of autonomic nervous system changes associated with generalized social phobia (GSP) disorder has increased in recent years, showing contradictory results. The present study aimed to evaluate how young people with GSP reacted before, during, and after exposure to the Trier Stress Social Test (TSST), focusing on their autonomic changes (heart rate variability (HRV) and salivary alpha-amylase (sAA)) compared to a control group (non-GSP). Some psychological variables were also considered. Sex was specifically studied as a possible modulator of autonomic fluctuations and psychological state. Eighty young people were randomly distributed into two counterbalanced situations: stress condi…
Chewing bread: impact on alpha-amylase secretion and oral digestion
2017
During chewing, saliva helps in preparing food bolus by agglomerating formed particles and initiates food enzymatic breakdown. However, limited information is actually available on the adaptation of saliva composition during oral processing of complex foods, especially for foods that are sensitive to salivary enzymes. We addressed this question in the context of starch–based products and salivary alpha-amylase. The objectives were two-fold: 1) determining if salivary alpha-amylase secretion can be modulated by bread type and 2) evaluating the contribution of the oral phase in bread enzymatic breakdown.Mouthfuls of three different wheat breads (industrial, artisan and whole breads) were chew…
Changes in different salivary biomarkers related to physiologic stress in elite handball players: the case of females
2019
AbstractThis study evaluates pre- and post-match concentrations of salivary cortisol, alpha-amylase (AA) and immunoglobulin A (lgA) in a group of 21 elite female handball players in the Spanish national women’s league. The players’ mean age was 23.0 ± 5.4 years. The concentration of the biomarkers was determined using ELISA. Mean playing time was 25.2 min. The players’ cortisol concentration increased significantly (p < 0.05) whereas the IgA concentration fell significantly (p < 0.01) at the end of the match. There were no significant changes in the concentrations of AA between pre and post-match timepoints. The changes observed in the study also depended on the position played; defen…
Acute stress and working memory in older people.
2015
Several studies have shown that acute stress affects working memory (WM) in young adults, but the effect in older people is understudied. As observed in other types of memory, older people may be less sensitive to acute effects of stress on WM. We performed two independent studies with healthy older men and women (from 55 to 77 years old) to investigate the effects of acute stress (Trier Social Stress Test; TSST) and cortisol on WM. In study 1 (n = 63), after the TSST women (but not men) improved their performance on Digit Span Forward (a measure of the memory span component of WM) but not on Digit Span Backward (a measure of both memory span and the executive component of WM). Furthermore,…
Stress Levels in Handball Coaching-Case Study: Preliminary Analysis of the Differences between Training and Match.
2022
Stress plays a significant role in competitions and in the training of sports participants, and coaches are no exception. To better cope with stressful situations, close monitoring of coaches’ stress levels before, during, and after training and competitions is recommended. According to studies, the use of cortisol (C) and alpha-amylase (AA) as biomarkers for monitoring acute stress is recommended. Therefore, the aim of our study was to compare HR, salivary C and AA, and STAI scores before, during, and after handball matches and training sessions. The study examined one professional handball coach, aged 37, in stress markers (salivary cortisol (C) and alpha-amylase (AA) concentrations…
Amylase–Trypsin Inhibitors in Wheat and Other Cereals as Potential Activators of the Effects of Nonceliac Gluten Sensitivity
2018
Nonceliac gluten sensitivity (NCGS) is a gluten-related gastrointestinal disorder distinct from celiac disease (CD) and gluten allergy that is not easy to diagnose due to the lack of biomarkers. It is characterized by intestinal symptoms and extraintestinal manifestations with the consumption of gluten-containing foods. In contrast to CD, NCGS patients do not present a genetic predisposition or intestinal villi atrophy. Recent studies question the proinflammatory triggering activity of α-gliadin fraction contained in wheat, since it has been demonstrated that the amylase-trypsin inhibitors (ATIs) exert a strong activating effect on the innate immune response. We aimed to analyze the role of…
Effects of Different Chair-Based Exercises on Salivary Biomarkers and Functional Autonomy in Institutionalized Older Women
2019
The aim of this study was to test the effects of chair-based exercise programs on salivary stress hormones, physical fitness, and functional autonomy of institutionalized older women.In total, 47 participants (80 ± 8.04 years old) were recruited and allocated into three groups: chair-based aerobic exercises (CAE, n = 19), chair-based elastic-band strength exercises (CSE, n = 15), and a control group (CG, n = 13). A 14-week exercise intervention was done for the CAE and CSE groups, two times per week, in no consecutive days. Members of the CG did not participate in any type of exercise but kept their regular lifestyle. Fear of falling, autonomy, physical fitness, salivary cortisol, and alpha…
Understanding phenolic acids inhibition of α-amylase and α-glucosidase and influence of reaction conditions
2022
Phenolic acids are involved in modulating the activity of starch digestive enzymes but remains unclear if their interaction with enzymes or starch is governing the inhibition. The potential inhibition of nine phenolic acids against α-amylase and α-glucosidase was studied applying different methodologies to understand interactions between phenolic acids and either enzymes or substrates. Vanillic and syringic acids were prone to interact with α-amylase requiring low half-maximum inhibitory concentration (IC50) to inhibit starch hydrolysis. Nevertheless, the initial interaction of phenolic acids with starch somewhat obstructed their interaction with starch, requiring 10 times higher IC50, with…
A feasibility study of application and potential effects of a single session transcranial Direct Current Stimulation (tDCS) on competitive anxiety, m…
2020
Objective : To examine feasibility and potential effects of a single session tDCS over the dorsolateral prefrontal cortex (DLPFC) on competitive anxiety, mood state, and autonomic and endocrine stress responses in elite archer athletes under a real world competition. Methods : Twelve male elite archers volunteered to participate in this pilot trial. Participants were randomized in order to take left anodal DLPFC, left cathodal DLPFC, or sham stimulation (the F3 or F4 areas according to the 10/20 EEG International System) in a within-subject study design. This study included three official competitions. About 45 min before the competition, the tDCS stimulation process was started and the par…