Dataset Information

Factors Affecting Measurement of Salivary Cortisol and Secretory Immunoglobulin A in Field Studies of Athletes.

ABSTRACT: Biological and lifestyle factors, such as daily rhythm, caffeine ingestion, recent infection, and antibiotic intake, have been shown to influence measurements of salivary cortisol (SC) and secretory immunoglobulin A (sIgA). Current methodology in unsynchronized, field-based biomarker studies does not take these effects into account. Moreover, very little is known about the combined effects of biological and lifestyle factors on SC and sIgA. This study supports development of a protocol for measuring biomarkers from saliva collected in field studies by examining the individual and combined effects of these factors on SC and sIgA.At three time points (start of the pre-season; start of playing season; and end of playing season), saliva samples were collected from the entire squad of 45 male players of an elite Australian Football club (mean age 22.8 ± 3.5 years). At each time, point daily rhythm and lifestyle factors were determined via a questionnaire, and concentrations of both SC and sIgA via an enzyme linked immuno-sorbent (ELISA) assay of saliva samples. In addition, player times to produce 0.5 mL of saliva were recorded.Analysis of covariance of the data across the three time points showed that daily rhythm had a more consistent effect than the lifestyle factors of caffeine ingestion, recent infection, and antibiotic intake on SC, but not on sIgA. Data for sIgA and SC concentrations were then adjusted for the effects of daily rhythm and lifestyle factors, and correlational analysis of the pooled data was used to examine the relative effects of these two sources of influence on sIgA and SC. With the exception of time to produce saliva, the biological measures of stress were affected by players' daily rhythms. When daily rhythm was taken into account the group of lifestyle factors did not have an additional effect.It is recommended that future studies measuring SC and sIgA make additional adjustments for the daily rhythm, in particular time since first sight of daylight, as small measurement errors of biomarkers can confound discrimination among study participants.

SUBMITTER: Pritchard BT

PROVIDER: S-EPMC5522838 | biostudies-other | 2017

REPOSITORIES: biostudies-other

ACCESS DATA

Similar Datasets

Project description:Highlights • Dried urine is an alternative to liquid urine for measuring cortisol and its metabolites.• 4-spot urine sampling is representative of a 24-hour urine collection.• 4-spot urinary cortisol measures reflect the diurnal pattern of change in cortisol.• Comprehensive profiling of cortisol is viable using both saliva plus dried urine samples. Aims/objectives The primary aim of this study was to determine the utility of dried urine sampling in obtaining measures of cortisol and cortisol metabolites. Additional aims were to evaluate if a 4-spot dried urine collection is representative of a 24-hour urine collection and if expected diurnal cortisol patterns can be observed in samples from both urine and saliva. Methods Data from individuals with cortisol measures available from both a 4-spot dried urine collection and a 24-hour urine collection (n = 28) were evaluated. Of these 28, 20 also had concurrent liquid and dried 24-hour urine measures. Consistency between these methods was evaluated using paired t-tests and intraclass correlation coefficients (ICCs). In addition, data from individuals with concurrent measures of both urinary and salivary cortisol (n = 68) were assessed for consistency in the diurnal pattern of change in cortisol. Results Near ideal consistency was observed between liquid and dried urine for measures of total urine free cortisol, total urine cortisone, and total cortisol metabolites (n = 20; ICCs = 0.99, 0.97 and 0.96, respectively). Good to excellent consistency was observed between the 4-spot method and the 24-hour collection (n = 28; ICCs = 0.89, 0.95 and 0.92, respectively). In mixed model analysis, no difference was seen in the diurnal pattern of cortisol between salivary and urinary free cortisol (n = 68; P = 0.83). Conclusion Dried urine is a viable alternative to liquid urine for the measurement of cortisol and cortisol metabolites. Additionally, if the 4 measures are added together, 4-spot urine collections can be representative of diurnal cortisol patterns commonly assessed using saliva and 24-hour urine collections.

Project description:Immediate freezing at -20°C or below has been considered the gold standard for microbiome preservation, yet this approach is not feasible for many field studies, ranging from anthropology to wildlife conservation. Here we tested five methods for preserving human and dog fecal specimens for periods of up to 8 weeks, including such types of variation as freeze-thaw cycles and the high temperature fluctuations often encountered under field conditions. We found that three of the methods-95% ethanol, FTA cards, and the OMNIgene Gut kit-can preserve samples sufficiently well at ambient temperatures such that differences at 8 weeks are comparable to differences among technical replicates. However, even the worst methods, including those with no fixative, were able to reveal microbiome differences between species at 8 weeks and between individuals after a week, allowing meta-analyses of samples collected using various methods when the effect of interest is expected to be larger than interindividual variation (although use of a single method within a study is strongly recommended to reduce batch effects). Encouragingly for FTA cards, the differences caused by this method are systematic and can be detrended. As in other studies, we strongly caution against the use of 70% ethanol. The results, spanning 15 individuals and over 1,200 samples, provide our most comprehensive view to date of storage effects on stool and provide a paradigm for the future studies of other sample types that will be required to provide a global view of microbial diversity and its interaction among humans, animals, and the environment. IMPORTANCE Our study, spanning 15 individuals and over 1,200 samples, provides our most comprehensive view to date of storage and stabilization effects on stool. We tested five methods for preserving human and dog fecal specimens for periods of up to 8 weeks, including the types of variation often encountered under field conditions, such as freeze-thaw cycles and high temperature fluctuations. We show that several cost-effective methods provide excellent microbiome stability out to 8 weeks, opening up a range of field studies with humans and wildlife that would otherwise be cost-prohibitive.

Project description:To investigate at what age preterm infants develop a salivary cortisol circadian rhythm and identify whether it is dependent on gestational age and/or postnatal age. To evaluate whether salivary cortisol circadian rhythm development is related to behavioral regularity. To elucidate salivary cortisol levels in preterm infants during the first year of life.This prospective, longitudinal study included 51 preterm infants. 130 healthy full-term infants served as controls. Monthly salivary cortisol levels were obtained in the morning (07:30-09:30), at noon (10:00-12:00), and in the evening (19:30-21:30), beginning at gestational age week 28-32 and continuing until twelve months corrected age. Behavioral regularity was studied using the Baby Behavior Questionnaire.A salivary cortisol circadian rhythm was established by one month corrected age and persisted throughout the first year. The preterm infants showed a cortisol pattern increasingly more alike the full-term infants as the first year progressed. The preterm infants increase in behavioral regularity with age but no correlation was found between the development of salivary cortisol circadian rhythm and the development of behavior regularity. The time to establish salivary cortisol circadian rhythm differed between preterm and full-term infants according to postnatal age (p = 0.001) and was dependent on gestational age. Monthly salivary cortisol levels for preterm infants from birth until twelve months are presented. Additional findings were that topical corticosteroid medication was associated with higher concentrations of salivary cortisol (p = 0.02) and establishment of salivary cortisol circadian rhythm occurred later in infants treated with topical corticosteroid medication (p = 0.02).Salivary cortisol circadian rhythm is established by one month corrected age in preterm infants. Establishment of salivary cortisol circadian rhythm is related to gestational age rather than to postnatal age. Salivary cortisol circadian rhythm development is not related to behavioral regularity.

Dataset Information

Factors Affecting Measurement of Salivary Cortisol and Secretory Immunoglobulin A in Field Studies of Athletes.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets