The type A behavior pattern and immune reactivity to brief stress: change of volume of secretory immunoglobulin A in saliva

Secretory Ig a in Saliva and Academic Stress

Several reports have proposed that the concentration of secretory immunoglobulin A (S-IgA) in saliva is an indicator of psychological stress. With this in mind, we decided to examine it in 10 second year medical student volunteers at Kawasaki Medical School course between May 4 and July 13, 2000 and discussed the relationship between S-IgA and the stress from academic examinations. Saliva was collected three times (on rising, at forenoon, and at bedtime) every Thursday. During this period, sporadic academic examinations were held twice and term-end examinations occurred during the last two weeks. Results showed the concentration of S-IgA significantly higher at the on rising time-point than at the other two time-points. There was also a tendency for the S-IgA level in saliva to be higher on the day before academic examinations and during them and lower on the days between these examinations. In addition, daily variations in the S-IgA concentration sometimes seemed to be disturbed by other academic stress. Therefore, it may be possible to use this measurement to monitor psychological stress in students and workers.

A randomized, double-blind, placebo-controlled trial of a traditional herbal formula, Yukmijihwang-tang in elderly subjects with xerostomia

ETHNOPHARMACOLOGICAL RELEVANCE

Yukmijihwang-tang (YMJ) is a typical herbal formula to treat Yin-deficiency (YD) syndrome by enriching the fluid-humor of the body. YMJ has been used to treat dry mouth symptoms for hundreds of years in traditional East Asian medicine. Xerostomia, a subjective oral dryness, is common in the elderly and results in impaired quality of life. Many conventional treatments for xerostomia provide only temporary symptom relief, and have side effects. The aim of this study is to investigate the efficacy and safety of YMJ for the treatment of xerostomia in the elderly.

METHODS

This study was designed as a randomized, placebo-controlled, double-blinded, two center trial. Ninety-six subjects aged 60-80 years who had experienced xerostomia for at least 3 months and presented with score>40 on the visual analog scale (VAS) for subjective oral dryness were recruited and randomly allocated to YMJ and placebo groups. YMJ or placebo was administered to each group for 8 weeks (3g of YMJ or placebo, three times per day). The primary outcome was change of VAS for xerostomia from 0 to 8 weeks.

RESULTS

VAS for xerostomia was decreased by 22.04±22.76 in the YMJ group and 23.58±23.04 in the placebo group. YMJ had no effect on xerostomia. However, participants with BMIs lower than 29.37kg/m(2) showed improvement of xerostomia after 8 weeks of treatment with YMJ compared to placebo. In addition, YMJ improved oral moisture, which is associated with subjective oral dryness in the YMJ group, and the relationship between VAS for xerostomia and YD was significant.

CONCLUSION

A trend was observed in which YMJ improved oral moisture status and subjective oral dryness in elderly subjects with lower BMI and greater tendency toward YD.

Perturbation of secretory Ig A in saliva and its daily variation by academic stress

OBJECTIVES

Several studies have reported that the secretory immunoglobulin A (S-IgA) concentration in saliva is an indicator of psychological stress. The aim of this study was to clarify the relationship between S-IgA and the stress from academic examinations.

METHODS

S-IgA levels in 10 medical student volunteers from the second year course between May 4 and July 13, 2000 were examined using the ELISA method.

RESULTS

There was a tendency for S-IgA in saliva to be higher on the day before academic examinations and during them, and lower on the days between these examinations.

CONCLUSIONS

It may be possible to use this measurement to monitor psychological stress in students and workers.

The impact of a 17-day training period for an international championship on mucosal immune parameters in top-level basketball players and staff members

This investigation examined the impact of a 17-d training period (that included basketball-specific training, sprints, intermittent running exercises, and weight training, prior to an international championship competition) on salivary immunoglobulin A (SIgA) levels in 10 subjects (athletes and staff members) from a national basketball team, as a biomarker for mucosal immune defence. Unstimulated saliva samples were collected at rest at the beginning of the preparation for the Pan American Games and 1 d before the first game. The recovery interval from the last bout of exercise was 4 h. The SIgA level was measured using enzyme-linked immunosorbent assay and expressed as absolute concentrations, secretion rate, and SIgA level relative to total protein. The decrease in SIgA levels following training was greater in athletes than in support staff; however, no significant differences between the two groups were detected. A decrease in SIgA level, regardless of the method used to express IgA results, was verified for athletes. Only one episode of upper respiratory tract illness symptoms was reported, and it was not associated with changes in SIgA levels. In summary, a situation of combined stress for an important championship was found to decrease the level of SIgA-mediated immune protection at the mucosal surface in team members, with greater changes observed in the athletes.

Physiological Effects of Shinrin-yoku (Taking in the Atmosphere of the Forest) in an Old-Growth Broadleaf Forest in Yamagata Prefecture, Japan

The physiological effects of "Shinrin-yoku" (taking in the atmosphere of the forest) were examined by investigating blood pressure, pulse rate, heart rate variability (HRV), salivary cortisol concentration, and immunoglobulin A concentration in saliva. Subjective feelings of being "comfortable", "calm", and "refreshed" were also assessed by questionnaire. The subjects were 12 male university students aged from 21 to 23 (mean+/-SD: 22.0+/-1.0). The physiological measurements were conducted six times, i.e., in the morning and evening before meals at the place of accommodation, before and after the subjects walked a predetermined course in the forest and city areas for 15 minutes, and before and after they sat still on a chair watching the scenery in the respective areas for 15 minutes. The findings were as follows. In the forest area compared to the city area, 1) blood pressure and pulse rate were significantly lower, and 2) the power of the HF component of the HRV tended to be higher and LF/(LF+HF) tended to be lower. Also, 3) salivary cortisol concentration was significantly lower in the forest area. These physiological responses suggest that sympathetic nervous activity was suppressed and parasympathetic nervous activity was enhanced in the forest area, and that "Shinrin-yoku" reduced stress levels. In the subjective evaluation, 4) "comfortable", "calm", and "refreshed" feelings were significantly higher in the forest area. The present study has, by conducting physiological investigations with subjective evaluations as supporting evidence, demonstrated the relaxing and stress-relieving effects of "Shinrin-yoku".

Relationships between physiological and psychological stress and salivary immunoglobulin A among young female gymnasts

We investigated whether psychological and physical stress induced by training or competition influence the secretory immune system among 12 highly trained young female gymnasts. Salivary levels of secretory IgA and cortisol responses to gymnastic training session or competition were assessed a total of 10 times, immediately before and after two training sessions which had different intensities and just before and after a major competition. These parameters were also measured on two non-training days. The Brunel Mood Scale was also used to assess the gymnasts's overall mood on each test day. IgA:Protein ratio was calculated. Significant decreases in this ratio were found after each exercise session, related to the physiological and psychological stress induced by exercise. Over the 5-mo. training period the presession IgA:Protein ratios were unchanged. Gymnasts registered any episodes of upper respiratory tract infection. Bouts of exercise induce transitory effects on the immune system in relation to the workload and the stress induced by the exercise without any relation to increased susceptibility to illness in children.

A Novel Method for Estimating the Adaptive Ability of Guide Dogs Using Salivary sIgA

Salivary secretory immunoglobulin A (sIgA) concentrations of prospective guide dogs for the blind were determined to clarify whether salivary sIgA is useful in evaluating the potential suitability of guide dogs for the blind. Saliva was collected from 73 prospective guide dogs in the kennel on day 1 (the day of separation from volunteer puppy-raisers), 2, 3, 7 and 14 during the estimation period (at about 1 year old). We selected particularly suitable dogs (superior dogs) and unsuitable dogs (inferior dogs) on the basis of the trainers' estimation. All dogs were divided into two groups, those were acceptable dogs would become the guide dogs and rejected dogs could not become guide dogs. The sIgA concentrations in superior dogs gradually increased from day 1 to 14 and those in inferior dogs remained at low levels. Moreover, the sIgA concentrations on day 14 in the acceptable dogs were significantly higher than those in rejected dogs. The cut-off point of sIgA concentrations on day 14 using an ROC curve was 90 EU/ml, and the specificity of the estimation at this point (70.4%) was higher than that of trainers' estimation (50%). Moreover, parallel testing using both trainers' estimation and sIgA estimation, showed that specificity was further improved (79.5%). The present study showed that sIgA concentration was extremely useful in estimating the adaptive ability for guide dogs for the blind.

Effects of expression and inhibition of negative emotions on health, mood states, and salivary secretory immunoglobulin A in Japanese mildly depressed undergraduates

Previous studies have indicated that expression of negative emotions facilitates mental and physical health and inhibition of negative emotions increases susceptibility to illness. This study was conducted to examine whether those findings can be expanded to populations with non-Western cultural backgrounds. Specifically, we explored effects of expression and inhibition of negative emotions on health, mood states, and mucosal immune function in mildly depressed Japanese individuals. 16 depressed and 16 nondepressed female undergraduates were required either to write about their unpleasant experiences and superficial topics or to suppress any emotional responses and thoughts about them. Secretory immunoglobulin A (s-IgA) in saliva and psychological indices were measured at an experimental session and at a follow-up 1 wk. later. Beneficial effects of expression of emotions on subjective health were indicated in the nondepressed group, whereas harmful effects of inhibition on subjective health were shown in the depressed group. Emotional expression by writing improved mood states both in the depressed and nondepressed groups but induced elevation of salivary s-IgA only in the depressed group.

Social support and salivary secretory immunoglobulin A response in women to stress of making a public speech

Acute experimental stressors transiently increase volume of secretory immunoglobulin A (s-IgA) in saliva. The present study examined buffering effects of social support on response of s-IgA to a brief psychological stress (giving a public speech). 24 women were divided at random into three groups, an emotional support group, an informational support group and a no-support group (control). For each group, s-IgA measures were obtained from each person under baseline conditions, during preparation of a speech when social support or no support was given, immediately after the speech and during a 'recovery' period. Level of s-IgA in the control group significantly elevated during preparation for the speech and just after the speech compared to baseline, suggesting that the speech task stimulated secretory immune function. On the other hand, the subjects in the emotional support group showed increased s-IgA during the preparation period but secretion of s-IgA rapidly returned to the baseline after the speech task. Secretion of s-IgA in the informational social support group was unchanged at any measurement point. These results suggest that social support attenuates the affect of a stressor on somatic state.

Psychological stress and the human immune system: a meta-analytic study of 30 years of inquiry

The present report meta-analyzes more than 300 empirical articles describing a relationship between psychological stress and parameters of the immune system in human participants. Acute stressors (lasting minutes) were associated with potentially adaptive upregulation of some parameters of natural immunity and downregulation of some functions of specific immunity. Brief naturalistic stressors (such as exams) tended to suppress cellular immunity while preserving humoral immunity. Chronic stressors were associated with suppression of both cellular and humoral measures. Effects of event sequences varied according to the kind of event (trauma vs. loss). Subjective reports of stress generally did not associate with immune change. In some cases, physical vulnerability as a function of age or disease also increased vulnerability to immune change during stressors.

Secretory immunoglobulin A reactivity to acute and cumulative acute multi-tasking stress: relationships between reactivity and perceived workload

The effects of an acute stressor upon secretory immunoglobulin A (S-IgA) were assessed using a task that requires participants to attend and respond to several stimuli simultaneously and is therefore analogous to a variety of working environments. In two studies, the task was administered for periods of 5 min to healthy samples of men and women at two sessions 24 h apart (n = 49) and three times in succession within one session (n = 20). Multi-tasking stress was, at all sessions, associated with increases in S-IgA secretion. Inter and intra-session reliability of pre and post-stress S-IgA measures was observed, although the reliability of stress reactivity data was reduced. Classification of participants as either high or low S-IgA reactors revealed differences in their perceptions of task workload. Low S-IgA reactors consistently perceived the task to be more demanding and frustrating than did those who demonstrated high S-IgA reactivity. We conclude that S-IgA reactivity to stressful situations depends not just upon the task, but also upon individual perceptions of the stressor.

Psychological stress and the human immune system: a meta-analytic study of 30 years of inquiry

The present report meta-analyzes more than 300 empirical articles describing a relationship between psychological stress and parameters of the immune system in human participants. Acute stressors (lasting minutes) were associated with potentially adaptive upregulation of some parameters of natural immunity and downregulation of some functions of specific immunity. Brief naturalistic stressors (such as exams) tended to suppress cellular immunity while preserving humoral immunity. Chronic stressors were associated with suppression of both cellular and humoral measures. Effects of event sequences varied according to the kind of event (trauma vs. loss). Subjective reports of stress generally did not associate with immune change. In some cases, physical vulnerability as a function of age or disease also increased vulnerability to immune change during stressors.

Effect of metabolic cage housing on immunoglobulin A and corticosterone excretion in faeces and urine of young male rats

Six 8-week-old Sprague-Dawley rats were studied for 9 days divided into three periods of 3 days each: before transferral to metabolism cages, during metabolic cage housing and after return to their home cages. Faeces were collected daily when the animals were housed in their home cages and every 6 h when the animals were housed in metabolic cages during which time urine was also collected every 6 h. The rate of weight gain was slightly reduced during the 3 days in metabolic cages and the animals produced significantly larger amounts of faeces when housed in metabolic cages than when housed in their home cages. The total faecal excretion of corticosterone (nanograms excreted per hour per kilogram body weight) and immunoglobulin A (IgA) (milligrams excreted per hour per kg body weight) quantified by enzyme-linked immunosorbent assays (ELISAs) exhibited a clear diurnal rhythm in the metabolic cage. Urinary excretions of corticosterone and IgA also followed a clear diurnal cycle. The mean daily amounts of corticosterone excreted were not significantly affected by cage change and by housing in metabolic cages. However, the excretion of faecal IgA was significantly reduced during the 3 days after the period in metabolic cages. Taken together the results indicate that metabolic cage housing is mildly stressful for young adult male rats.

Secretory immunoglobulin A reactions to prolonged mental arithmetic stress: inter-session and intra-session reliability

Although previous evidence suggests that mucosal immunity may be influenced by mental stress, the importance of the duration of stress exposure on secretory immunoglobulin A (sIgA) has yet to be fully elucidated. Salivary sIgA and cardiovascular activity were measured at rest, following 14 and 28 min of mental arithmetic, and after recovery in 24 men and women on two sessions 2-4 days apart. Mental arithmetic was, on both sessions and after both the early and late phases of the task, associated with increases in sIgA concentration and sIgA secretion rate compared to rest and recovery. Task levels of sIgA concentration and sIgA secretion rate showed moderate to high intra- and inter-session test-retest reliability, while test-retest reliability was lower for change scores. Blood pressure and pulse rate were also elevated by the mental stress task, although correlational analyses revealed that stress-induced changes in sIgA were not related to cardiovascular reactions.