Salivary Salivary Secretory Immunoglobulin A Research Articles

Thermal stress, hydration, and salivary and respiratory stress markers in curling players performing a match in the cold.

Curling is a target-based team sport played in a cold environment. The type of stress curling players face during a curling match remains to be determined. In the present study, 16 Japanese curling players performed a practice curling match (six ends lasting 90 min), wherein the following variables were documented: core and skin temperatures, heart rate, thermal sensation and comfort, urine-specific gravity, body fluid loss, salivary cortisol, α-amylase activity, salivary secretory immunoglobulin A (SIgA), and fractionated exhaled nitric oxide (FeNO, a respiratory stress marker). Pre-match resting core temperature was 37.24 ± 0.31°C, which increased up to 37.73 ± 0.41°C during the match (p < 0.001). Facial skin temperatures decreased after the match (all p ≤ 0.015), whereas finger skin temperatures remained unchanged (p ≥ 0.375). Thermal discomfort increased following the match but thermal sensation remained unchanged. Following the match, players lost 0.29 ± 0.15 L body fluid (sweat, respiratory evaporation, and urine), which was nearly compensated by fluid ingestion of 0.22 ± 0.13 L (p = 0.119). Nevertheless, urine-specific gravity increased from 1.021 ± 0.010 to 1.024 ± 0.008 after the match (p = 0.012), with 31% and 50% players being dehydrated at pre- and post-match, respectively. Salivary cortisol decreased (p < 0.001) after the match without changes in salivary SIgA, α-amylase activity, and FeNO (all p ≥ 0.113). Therefore, during a curling match, the core temperature and thermal discomfort increase, whereas the face skin temperature decreases. Additionally, players may undergo dehydration before the match, which could be exacerbated after the match.

Child Salivary SIgA and Its Relationship to Enteric Infections and EED Biomarkers in Maputo, Mozambique.

Characterizing child immunological responses to enteric infections with antibody detection in serum can be challenging in resource-constrained field settings, because sample collection requires trained individuals and its invasive procedure may lead to low response rates, especially among children. Saliva may present a promising non-invasive alternative. The objectives of this research were to compare salivary antibody levels in children to enteric infections and biomarkers of environmental enteric dysfunction (EED). We collected saliva samples from children aged one to six years enrolled in a sanitation trial in Maputo, Mozambique, and characterized salivary secretory immunoglobulin A (SIgA) concentrations with enzyme-linked immunosorbent assays. We used multilevel linear models to analyze cross-sectional associations between salivary SIgA and the number of concurrent enteric pathogen infections, as well as EED biomarkers in matched stool samples. Median salivary SIgA concentrations in this study population were 54 μg/mL (inter-quartile range (IQR): 34, 85 μg/mL), and SIgA levels were similar between children of different ages. SIgA was lower in children experiencing a higher number of concurrent infections −0.04 log μg/mL (95% confidence interval (CI): −0.08 to −0.005 log μg/mL), but was not associated with any of the included EED biomarkers. Contrary to evidence from high-income countries that suggests salivary SIgA increases rapidly with age in young children, the high prevalence of enteric infections may have led to a suppression of immunological development in this study sample and could in part explain the similar SIgA levels between children of different ages.

Effects of oral stimulation with capsaicin on salivary secretion and neural activities in the autonomic system and the brain

Background/purposeAlthough it has been reported that capsaicin ingestion has effects of protecting stomach mucosa and promoting energy consumption, physiological responses to oral stimulation with capsaicin has not been elucidated. Therefore, we investigated the effect of oral capsaicin stimulation on oral health and mental conditions by measuring changes in salivation, autonomic nervous activity and electroencephalogram (EEG). Materials and methodsEighteen healthy adults participated in this study. The stimulus concentrations of capsaicin and five basic taste solutions were determined based on the measured threshold of each stimulus in each subject. The weight of secreted saliva and the changes in concentrations of salivary secretory immunoglobulin A (SIgA) induced by capsaicin and taste stimuli were measured. Salivary α-amylase activity and heart rate variability (HRV) were measured as indicators of autonomic nervous activity. From EEG, psychological condition was analyzed by measuring the powers of theta, alpha, and beta bands. ResultsThe salivary secretion rate was significantly increased by stimulation with capsaicin, NaCl, and citric acid compared with deionized water, and capsaicin demonstrated the most potent effect among tested stimuli. The secreted amount of SIgA per minute was elevated by capsaicin stimulation. Salivary α-amylase activity and HRV analysis demonstrated an elevation of sympathetic nervous activity induced by capsaicin. EEG analysis showed a significant increase in beta band power. ConclusionThese results suggest that oral stimulation with capsaicin may be effective in improving oral conditions by increasing salivary flow and SIgA secretion, and in enhancing physical and mental conditions as indicated by sympathetic nerve and EEG changes.

Salivary extracellular heat shock protein 70 (eHSP70) levels increase after 59 min of intense exercise and correlate with resting salivary secretory immunoglobulin A (SIgA) levels at rest.

This study aimed to identify the response of a salivary stress protein, extracellular heat shock protein (eHSP70), to intense exercise and to investigate the relationship between salivary eHSP70 and salivary immunoglobulin A (SIgA) levels in response to exercise. Sixteen healthy sedentary young males (means ± SD 23.8 ± 1.5 years, 172.2 ± 6.4 cm, 68.3 ± 7.4 kg) performed 59 min of cycling exercise at 75% VO2max. Saliva and whole blood samples were collected before (Pre), immediately after (Post), and at 1, 2, 3, and 4 h after completion of the exercise (1, 2, 3, and 4 h). The salivary eHSP70 and SIgA levels were measured by enzyme-linked imunosorbent assay (ELISA), and the secretion rates were computed by multiplying the concentration by the saliva flow rate. White blood cells were analyzed using an automated cell counter with a direct-current detection system. The salivary eHSP70 secretion rates were 1.11 ± 0.86, 1.51 ± 1.47, 1.57 ± 1.32, 2.21 ± 2.04, 3.36 ± 2.72, and 6.89 ± 4.02 ng · min(-1) at Pre, Post, and 1, 2, 3, and 4 h, respectively. The salivary eHSP70 secretion rate was significantly higher at 4 h than that at Pre, Post, 1, and 3 h (p < 0.05). The SIgA secretion rates were 26.9 ± 12.6, 20.3 ± 10.4, 19.6 ± 11.0, 21.8 ± 12.8, 21.5 ± 11.9, and 21.9 ± 11.7 μg · min(-1) at Pre, Post, 1, 2, 3, and 4 h, respectively. The salivary SIgA secretion rate was significantly lower between 1 and 4 h than that at Pre (p < 0.05). There was a positive correlation between salivary eHSP70 and SIgA in both concentration and secretion rates before exercise (p < 0.05). The absolute number of white blood cells significantly increased after exercise, with a maximum at 2 h (p < 0.05). The neutrophil/lymphocyte ratio was significantly increased from 1 to 4 h when compared with that in the Pre samples (p < 0.05). The present study revealed that salivary eHSP70 significantly increased at 4 h after the 59 min of intense exercise in sedentary male subjects. Exercise stress can induce elevated salivary eHSP70 level and upregulate oral immune function partially.

Salivary SIgA responses to acute moderate-vigorous exercise in monophasic oral contraceptive users.

The purpose of this study was to examine the effect of oral contraceptive (OC) use on salivary secretory immunoglobulin A (SIgA) levels at rest and in response to an acute bout of moderate-vigorous exercise during 2 phases of the 4-week OC cycle corresponding to different phases of the synthetic menstrual cycle. Ten healthy active females completed a cycling at 70% peak oxygen uptake for 45 min at 2 time points of an OC cycle: during the equivalent in time to the mid-follicular phase (day 8 ± 2) and the mid-luteal phase (day 20 ± 2). Timed unstimulated saliva samples were obtained before, immediately postexercise, and 1 h postexercise and analyzed for salivary SIgA. Salivary SIgA secretion rate was 26% (95% confidence limits (CI) 6-46) lower at postexercise compared with pre-exercise during the synthetic follicular phase (p = 0.019) but no differences were observed during the synthetic luteal trial. Saliva flow rate was 11% (95% CI, 8-30) lower at postexercise compared with pre-exercise (main effect for time; p = 0.025). In conclusion, the pattern of salivary SIgA secretion rate response to moderate-vigorous exercise varies across the early and late phases of a monophasic OC cycle, with a transient reduction in salivary SIgA responses during the synthetic follicular phase. These findings indicate that monophasic OC use should be considered when assessing mucosal immune responses to acute exercise.

Influence of a probiotic Lactobacillus casei strain on the colonisation with potential pathogenic streptococci and Staphylococcus aureus in the nasopharyngeal space of healthy men with a low baseline NK cell activity.

The effect of a daily intake of the probiotic strain Lactobacillus casei Shirota (LcS) on the colonisation of pathogens, specifically streptococci and Staphylococcus aureus, in the nose and throat of healthy human volunteers with low natural killer cell activity, was investigated in a randomised and controlled intervention study. The study consisted of a 2-week run-in phase, followed by a 4-week intervention phase. The probiotic treatment group received a fermented milk drink with LcS, while the placebo group received an equally composed milk drink without the probiotic additive. To isolate potential pathogenic streptococci and Staph. aureus, samples from the pharynx, as well as of both middle nasal meati, were taken, once after the run-in phase and once at the end of the intervention phase. Isolated bacteria were identified as either Staph. aureus and α- or β-haemolytic streptococci in a polyphasic taxonomical approach based on phenotypic tests, amplified ribosomal DNA restriction analysis genotyping, and 16S rRNA gene sequencing of representative strains. Salivary secretory immunoglobulin A (SIgA) was used as marker of protective mucosal immunity to evaluate whether LcS treatment influenced SIgA production. No statistically significant effect could be determined for intervention with LcS on the incidence of Staph. aureus in the nasal space, Staph. aureus in the pharyngeal space or for β-haemolytic streptococci and Streptococcus pneumoniae in the pharyngeal space. Thus, the intervention did not influence the nasopharyngeal colonisation with Gram-positive potential pathogens. Production of salivary SIgA as a potential means of microbiota modulation was also not affected.

The change in the amount of immunoglobulins as a response to stress experienced by soldiers on a peacekeeping mission

Recent studies have demonstrated various changes in systemic and mucosal immunity in people undergoing psychological stress. This study was designated for an assay of associations between the stress experienced by Lithuanian soldiers as a response to changed job conditions (deployment to Afghanistan) and level of immunoglobulins. Salivary and sera immunoglobulin concentrations were assessed and compared before and after the military mission; the associations between the deployment-related stress and the immunoglobulin level were examined. Special questionnaires covering state of health and strain experienced were used. Quantitative detection of immunoglobulins was performed by sandwich ELISA. Comparison of the medians at three time points (before, after the deployment and 1year after the mission) showed an increased level of salivary secretory immunoglobulin A (S-IgA) in association with deployment. Chi-square test of independence indicated statistically significant relationship between the stress and S-IgA amount. Correlation analysis using different health control methods revealed masked fear of soldiers to be expelled from the military service. The results indicated that salivary S-IgA is the most sensitive representative of mucosal immunity system to psychological stress related to changed job conditions in military service.

Chlorella intake attenuates reduced salivary SIgA secretion in kendotraining camp participants

BackgroundThe green alga Chlorella contains high levels of proteins, vitamins, and minerals. We previously reported that a chlorella-derived multicomponent supplement increased the secretion rate of salivary secretory immunoglobulin A (SIgA) in humans. Here, we investigated whether intake of this chlorella-derived supplement attenuated the reduced salivary SIgA secretion rate during a kendo training camp.MethodsTen female kendo athletes participated in inter-university 6-day spring and 4-day summer camps. They were randomized into two groups; one took placebo tablets during the spring camp and chlorella tablets during the summer camp, while the other took chlorella tablets during the spring camp and placebo tablets during the summer camp. Subjects took these tablets starting 4 weeks before the camp until post-camp saliva sampling. Salivary SIgA concentrations were measured by ELISA.ResultsAll subjects participated in nearly all training programs, and body-mass changes and subjective physical well-being scores during the camps were comparable between the groups. However, salivary SIgA secretion rate changes were different between these groups. Salivary SIgA secretion rates decreased during the camp in the placebo group (before vs. second, middle, and final day of camp, and after the camp: 146 ± 89 vs. 87 ± 56, 70 ± 45, 94 ± 58, and 116 ± 71 μg/min), whereas no such decreases were observed in the chlorella group (121 ± 53 vs. 113 ± 68, 98 ± 69,115 ± 80, and 128 ± 59 μg/min).ConclusionOur results suggest that a use of a chlorella-derived dietary supplement attenuates reduced salivary SIgA secretion during a training camp for a competitive sport.

Mucosal Immune Function Comparison Between Amenorrheic and Eumenorrheic Distance Runners

This study examined the effects of amenorrhea on mucosal immune function and susceptibility to upper respiratory tract infection (URTI) in elite female distance runners. Based on their menstrual cycles during the prior year, 21 elite, collegiate, female distance runners were designated as eumenorrheic runners (ERs; n = 8; 19.9 ± 0.8 years) or amenorrheic runners (ARs; n n = 13; 20.0 ± 0.3 years). Resting saliva and blood samples were collected in the morning. The secretory immunoglobulin A (SIgA) concentration was measured using enzyme-linked immunosorbent assay. The SIgA secretion rate was calculated. Serum 17β-estradiol concentrations and serum progesterone concentrations were measured using radioimmunoassay. Subjects reported the appearance of URTI symptoms (sore throat, headache, runny nose, coughing, or fever), if any, during the prior month. The serum estradiol concentration and salivary SIgA secretion rate were significantly lower for ARs than for ERs (p < 0.05). Serum progesterone concentration was not significantly different between groups. Higher frequencies of headache, runny nose, coughing, and fever were observed in ARs than in ERs. Results show that athletic amenorrhea with low estrogen might accelerate downregulation of mucosal immune function in athletes and enhance susceptibility to infection.

Salivary Secretory Immunoglobulin a secretion increases after 4-weeks ingestion of chlorella-derived multicomponent supplement in humans: a randomized cross over study

BackgroundChlorella, a unicellular green alga that grows in fresh water, contains high levels of proteins, vitamins, minerals, and dietary fibers. Some studies have reported favorable immune function-related effects on biological secretions such as blood and breast milk in humans who have ingested a chlorella-derived multicomponent supplement. However, the effects of chlorella-derived supplement on mucosal immune functions remain unclear. The purpose of this study was to investigate whether chlorella ingestion increases the salivary secretory immunoglobulin A (SIgA) secretion in humans using a blind, randomized, crossover study design.MethodsFifteen men took 30 placebo and 30 chlorella tablets per day for 4 weeks separated by a 12-week washout period. Before and after each trial, saliva samples were collected from a sterile cotton ball that was chewed after overnight fasting. Salivary SIgA concentrations were measured using ELISA.ResultsCompliance rates for placebo and chlorella ingestions were 97.0 ± 1.0% and 95.3 ± 1.6%, respectively. No difference was observed in salivary SIgA concentrations before and after placebo ingestion (P = 0.38). However, salivary SIgA concentrations were significantly elevated after chlorella ingestion compared to baseline (P < 0.01). No trial × period interaction was identified for the saliva flow rates. Although the SIgA secretion rate was not affected by placebo ingestion (P = 0.36), it significantly increased after 4-week chlorella ingestion than before intake (P < 0.01).ConclusionsThese results suggest 4-week ingestion of a chlorella-derived multicomponent supplement increases salivary SIgA secretion and possibly improves mucosal immune function in humans.

Salivary SIgA and dental caries activity

This case-control study was conducted to determine the protective role of salivary secretory immunoglobulin A (SIgA) levels in the unstimulated whole saliva of dental caries active (Group I and II) and caries free children (Group III). Thirty children aged 4-8 years were selected. Their DMFT (Decayed Missing Filled teeth for permanent teeth) and/or df-t (decayed, filled teeth for deciduous teeth) scores were determined and the salivary SIgA levels were measured using Immunoturbidometry. SIgA levels of all three groups were in the the normal range of 4-30 mg/dL. The SIgA levels for both Group I and II were less than that in Group III (P=0.018 and P=0.0013, respectively).

Salivary Secretory Immunoglobulin A Response of Elite Speed Skaters During a Competition Period

We aimed to determine the responses of salivary secretory immunoglobulin A (SIgA) and the incidence of upper respiratory tract infections (URTI) symptoms among elite speed skaters during an actual competition period. The subjects were 8 international-class elite speed skaters. Saliva samples were obtained 3, 2, and 1 days before the race, the day of the race, and 1 day after the race. Salivary secretory immunoglobulin A concentration was measured by enzyme immunoassay, and SIgA secretion rate was calculated. A visual analogue scale was used to subjectively assess fatigue and tension. Daily URTI symptoms were recorded by using a questionnaire. There was no statistically significant difference in the saliva flow rate (p = 0.69), SIgA concentration (p = 0.07), and subjective fatigue (p = 0.07) during the competition period. The SIgA secretion rate recorded for the day of the race was significantly high compared with that of 3 and 2 days before and 1 day after the race (p < 0.05). The subjective tension recorded on the race day was significantly high compared with that for 3, 2, and 1 days before the race (p < 0.05). Two subjects exhibited URTI symptoms after the race. These findings suggest that salivary SIgA in elite speed skaters increased after a tapering period and that an actual high-intensity speed skating race decreased salivary SIgA in elite speed skaters. These data also suggest that the incidence of URTI symptoms might be related to the SIgA level. Coaches may need to take precautions after competitions to minimize their athletes' contact with cold viruses and adjust training load for a few days after competition to improve the decreased mucosal immune function.