Cytokines in Saliva. Basal Concentrations and the Effect of High Ambient Heat (Sauna)

Abstract

The aim of this study is to investigate the presence of several interleukins in saliva and how their concentrations may be modified after physical stress. The effects of one kind of somatic stress (sauna heat) on the concentrations of salivary cytokines were studied using ELISA assay. In addition, saliva cortisol was assayed. Fourteen volunteers participated in this study. Each subject attended one control and one stress session which took place at the same hour on different days. Saliva was collected on the control day immediately after a 15‐min rest period in a seated position (R1), and again after an additional 30‐min seated period (R2). On the test day, saliva was collected after 15 min of sitting (S1) and 30 min later (S2) following exposure to the heat of a sauna (90°C, 10 min, 40 per cent humidity). We found that saliva contains the multifunctional polypeptide cytokines interleukin‐1β, tumour necrosis factor alpha and the receptor for interleukin‐2 with the basal mean concentrations (geometric mean; SD in parenthesis) of 172 (106; 148) ng/l, 46 (20; 67) ng/l and 9 (6; 7) pM, respectively. Interleukin‐6 was detectable in only 60 per cent of the specimens investigated. Interleukin‐2 and the receptor for interleukin‐6 were not detectable. We examined the statistical differences between the ratio R2/R1 (the changes which occurred during the resting period) and S2/S1 (the changes during the exposure to heat). We observed a significantly higher S2/S1 ratio for the tumour necrosis factor alpha in males, compared to the control ratio (2.5±2.4 versus 0.7±0.7,N=6,p<0.05 using the Wilcoxon signed rank test). Our results indicate that a situation which induced an elevated body temperature was associated with a rise in the concentration of the salivary tumour necrosis factor alpha.

Salivary markers of inflammation in response to acute stress

“…Dugue et al (1996) exposed 14 “subjectively healthy” participants (mean age 34.5 years; 57% female, n = 8) to the heat of a sauna for 10 minutes (at 90°C with 40% humidity) and to a control resting condition on a different day (order was randomized). On the stressor day, saliva samples were taken after a 15 minute resting baseline period, which started at 6:30pm, and then immediately after the completion of the 10 minute sauna heat exposure.…”

“…To find these articles, combinations of the search terms “stress,” “acute,” “saliva,” “salivary,” “cytokine,” “inflammation,” “CRP,” and “interleukin” were entered into the US National Library of Medicine National Institutes of Health (PubMed) database. Four of the 13 articles (Groer et al, 2010; Lester et al, 2010; Mastrolonardo et al, 2007; Zefferino et al, 2006) were found from these search terms, and the additional nine references (Campisi et al, 2012; Dugue et al, 1996; Filaire et al, 2010; Ilardo et al, 2001; Izawa et al, 2013; Mahmood & Ibrahim, 2013; Minetto et al, 2005; Minetto et al, 2007; Usui et al, 2012) were found from the references or related references of these first four articles.…”

“…A small number of empirical studies ( n = 13; Campisi et al, 2012; Dugue et al, 1996; Filaire et al, 2010; Groer et al, 2010; Ilardo et al, 2001; Izawa et al, 2013; Lester et al, 2010; Mahmood & Ibrahim, 2013; Mastrolonardo et al, 2007; Minetto et al, 2005; Minetto et al, 2007; Usui et al, 2012; Zefferino et al, 2006) have investigated markers of inflammation in saliva in response to an acute stressor, using a variety of specific analytes: interleukin (IL)-1β, tumor necrosis factor (TNF)-α, IL-6, IL-2, IL-4, IL-10, IL-12, and C-reactive protein (CRP). These studies have assessed different biomarkers, employed varying timelines and collection techniques, reported different detectability limits, and utilized different stressors.…”

Vitamin C Supplementation Reduces Exercise-Induced Oxidative Stress and Increases Peak Muscular Force

“…No other descriptive data from participants were controlled. Participants had to be in good health to be included in the study; common colds, illnesses, smoking, kidney disorders, and iron-metabolism disorders excluded participants from the study as each can alter systemic vitamin C and salivary results [26] [27]. Participants were asked to maintain regular diet and exercise patterns throughout the duration of the study.…”

Effects of psycho-physical stress (competitive rafting) on saliva interleukin-1 beta

“…2,3 Moreover, cytokines have been supposed to be involved in the physiological regulation of sleep and wakefulness. 4 We have previously showed that saliva concentrations of tumor necrosis factor (TNF˛) and IL-1ˇwere elevated in high ambient heat 5 and after an audiovisual colour conflict test, 6 respectively. Furthermore, salivary sampling has the advantage of being a non-invasive procedure, unlike blooddrawing which introduces an additional stress component.…”