scholarly journals Do follicles matter? Testing the effect of follicles on hair cortisol levels

2020 ◽  
Vol 8 (1) ◽  
Author(s):  
Agnieszka Sergiel ◽  
Marc Cattet ◽  
Luciene Kapronczai ◽  
David M Janz ◽  
Nuria Selva ◽  
...  
Keyword(s):  
Mixed Model ◽  
Linear Mixed Model ◽  
Hair Follicles ◽  
Hair Cortisol ◽  
Mammal Species ◽  
Active Growth ◽  
Hair Samples ◽  
Cortisol Levels ◽  
Free Ranging ◽  
Collection Methods

Abstract Cortisol concentrations in hair are used increasingly as a biomarker of long-term stress in free-ranging wildlife. Cortisol is believed to be integrated into hair primarily during its active growth phase, typically occurring over weeks to months or longer periods, depending on latitude. Cortisol concentrations in hair thus reflect the activity of the hypothalamic–pituitary–adrenal axis over this time. However, local, independent cortisol secretion within the skin, which includes hair follicles, may also contribute to cortisol levels in growing hair. Methodological differences between studies include the measurement of cortisol in only the hair shaft (i.e. follicle absent, as with shaved hair) versus the whole hair (i.e. follicle present, as with plucked hair). If the concentration of cortisol in the follicle is high enough to influence the overall hair cortisol concentration (HCC), this could confound comparisons between studies using different types of hair samples (hair shafts vs. whole hair) and collection methods. Here, we test the hypothesis that cortisol present in follicles influences HCC. We compared HCC in paired subsamples of hair with and without follicles from 30 free-ranging Scandinavian brown bears (Ursus arctos) and observed significantly greater HCC in samples with follicles present. The effect of follicles remained significant also with sex and age of sampled bears taken into account in a linear mixed model. Finally, we provide an overview of collection methods and types of hair samples used for HCC analysis in 77 studies dealing with stress in wild mammal species. Our findings highlight the need to unify methods of hair collection and preparation to allow for valid comparisons, and to optimize labour input in ecophysiological studies.

scholarly journals Behavioral repeatability and foraging performance in wild free-flying nectarivorous bats (Glossophaga commissarisi)

2018 ◽  
Author(s):  
Vladislav Nachev ◽  
York Winter
Keyword(s):  
Individual Differences ◽  
Mixed Model ◽  
Linear Mixed Model ◽  
Field Investigation ◽  
Foraging Efficiency ◽  
Behavioral Measures ◽  
Foraging Performance ◽  
Patterns Of Behavior ◽  
Artificial Flowers ◽  
Free Ranging

ABSTRACTAnimal individuals show patterns of behavior that are stable within individuals but different among individuals. Such individual differences are potentially associated with differences in foraging efficiency and in fitness. Furthermore, behavioral responses may be correlated in specific suites of so called behavioral syndromes that are consistent across different contexts and with time. Here we present a field investigation on individual differences between wild, free-flying nectarivorous bats (Glossophaga commissarisi) in the foraging context. We further investigated how individual differences effect foraging performance, and we examined their interdependence within hypothesized behavioral syndrome structures. Free-ranging bats were individually identified as they visited an array of 24 artificial flowers with nectar of high or low sugar concentration. We found that three behavioral measures of foraging behavior were individually stable over the two-month observation period. We investigated the link between individual behavioral measures and measures of foraging performance using generalized linear mixed models. Individual measures of foraging performance showed significant repeatability, and we found evidence that bats making more visits per bout tend to be slower in learning to avoid unprofitable flowers. We used a multi-response generalized linear mixed model to estimate between-individual correlations and compare hypothesized syndrome structures. There were no clear patterns of between-individual correlations among the behavioral measures in our study, despite the measures exhibiting significant repeatability. This may indicate that foraging performance depends on multiple individual behavior dimensions that are not adequately described by simple models of behavior syndromes.

scholarly journals Hair cortisol-a method to detect chronic cortisol levels in patients with Prader-Willi syndrome

2020 ◽  
Author(s):  
Hasanain Hamid Shukur ◽  
Yolanda B de Rijke ◽  
Elisabeth FC van Rossum ◽  
Laith Hussain-Alkhateeb ◽  
Charlotte Höybye
Keyword(s):  
Linear Regression ◽  
Regression Model ◽  
Behavioral Problems ◽  
Linear Regression Model ◽  
Neurodevelopmental Disorder ◽  
Prader Willi Syndrome ◽  
Hair Cortisol ◽  
Hair Samples ◽  
Cortisol Levels

Abstract Background: Prader-Willi syndrome (PWS) is a multisymptomatic, rare, genetic, neurodevelopmental disorder in adults mainly characterized by hyperphagia, cognitive dysfunction, behavioral problems and risk of morbid obesity. Although endocrine insufficiencies are common, hypocortisolism is rare and knowledge on long-term cortisol concentrations is lacking. The aim of this study was to evaluate long-term cortisol levels in PWS by measurements of hair cortisol. Methods: Twenty-nine adults with PWS, 15 men and 14 women, median age 29 years, median BMI 27 kg/m2, were included. Scalp hair samples were analyzed for cortisol content using liquid-chromatography tandem-mass spectrometry. In addition, a questionnaire on auxology, medication and stress were included. For comparison, 105 age- and sex-matched participants from the population-based Lifelines Cohort study were included as controls. The mean hair cortisol between the groups were compared and associations between BMI and stress were assessed by a generalized linear regression model. Results: In the PWS group large variations in hair cortisol was seen. Mean hair cortisol was 12.8±25.4 pg/mg compared to 3.8±7.3 pg/mg in controls (p=0.001). The linear regression model similarly showed higher cortisol levels in patients with PWS, which remained consistent after adjusting for BMI and stress (p=0.023). Furthermore, hair cortisol increased with BMI (p=0.012) and reported stress (p=0.014). Conclusion: Long-term cortisol concentrations were higher in patients with PWS compared to controls and increased with BMI and stress, suggesting an adequate cortisol response to chronic stress. Hair cortisol demonstrate promising applications in the context of PWS treatment and disease management.

scholarly journals Scalp hair sweating as a predictor of hair cortisol level in human compared to obesity and other confounders

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Darya S. Abdulateef
Keyword(s):  
Cortisol Level ◽  
Scalp Hair ◽  
Positive Association ◽  
Stressful Events ◽  
Hair Cortisol ◽  
Significant Positive Association ◽  
Factors Affecting ◽  
Hair Samples ◽  
Cortisol Levels ◽  
Study Participants

AbstractInconsistent results were found throughout the literature regarding factors affecting hair cortisol levels. Hair cortisol level in humans was not studied for its associations to scalp hair sweating or hair wash frequency in a patient-based way. Factors affecting hair cortisol levels must be precisely known in order to interpret the results correctly. The aims of the study are to assess if BMI, Perceived Stress Scale (PSS), hair wash frequency, and sweating with scalp hair affect hair cortisol levels. It will assess which of these factors are more significant predictors of hair cortisol levels. In a study on healthy adults, information about history, socio-demographics, PSS, hair wash frequency, hair treatment, and scalp hair sweating were collected, and hair samples were taken and analyzed for their hair cortisol level. Associations of hair cortisol levels with each of the variables were investigated and significant predictors of hair cortisol levels among the variables were found. Mean hair cortisol level in the study participants was 16.84 pg/mg hair. Hair cortisol has a significant positive association with weight, BMI, PSS, and scalp hair sweating, p < 0.05. Scalp hair sweating significantly predicts hair cortisol levels by 12.3%, while other variables did not significantly predict hair cortisol levels, p < 0.05. Scalp hair sweating significantly predicts hair cortisol levels. Age, hair wash frequency, hair treatment, and stressful events have no associations with hair cortisol levels. Although BMI and PSS are associated with hair cortisol levels, they do not significantly predict it. Obesity is significantly associated with profuse sweating, thus the increase in hair cortisol levels in obese individuals could partly be the result of a higher incidence of sweating in these individuals. Thus, scalp hair sweating should be taken into consideration during the study and interpretation of hair cortisol levels.

scholarly journals Hair cortisol-a method to detect chronic cortisol levels in patients with Prader-Willi syndrome

2020 ◽  
Author(s):  
Hasanain Hamid Shukur ◽  
Yolanda B de Rijke ◽  
Elisabeth FC van Rossum ◽  
Laith Hussain-Alkhateeb ◽  
Charlotte Höybye
Keyword(s):  
Linear Regression ◽  
Regression Model ◽  
Behavioral Problems ◽  
Linear Regression Model ◽  
Neurodevelopmental Disorder ◽  
Prader Willi Syndrome ◽  
Hair Cortisol ◽  
Hair Samples ◽  
Cortisol Levels

Abstract Background: Prader-Willi syndrome (PWS) is a multisymptomatic, rare, genetic, neurodevelopmental disorder in adults mainly characterized by hyperphagia, cognitive dysfunction, behavioral problems and risk of morbid obesity. Although endocrine insufficiencies are common, hypocortisolism is rare and knowledge on long-term cortisol concentrations is lacking. The aim of this study was to evaluate long-term cortisol levels in PWS by measurements of hair cortisol.Methods: Twenty-nine adults with PWS, 15 men and 14 women, median age 29 years, median BMI 27 kg/m2, were included. Scalp hair samples were analyzed for cortisol content using liquid-chromatography tandem-mass spectrometry. In addition, a questionnaire on auxology, medication and stress were included. For comparison, 105 age- and sex-matched participants from the population-based Lifelines Cohort study were included as controls. The mean hair cortisol between the groups were compared and associations between BMI and stress were assessed by a generalized linear regression model.Results: In the PWS group large variations in hair cortisol was seen. Mean hair cortisol was 12.8±25.4 pg/mg compared to 3.8±7.3 pg/mg in controls (p=0.001). The linear regression model similarly showed higher cortisol levels in patients with PWS, which remained consistent after adjusting for BMI and stress (p=0.023). Furthermore, hair cortisol increased with BMI (p=0.012) and reported stress (p=0.014).Conclusion: Long-term cortisol concentrations were higher in patients with PWS compared to controls and increased with BMI and stress, suggesting an adequate cortisol response to chronic stress. Hair cortisol demonstrate promising applications in the context of PWS treatment and disease management.

scholarly journals Longitudinal Associations between Hair Cortisol, PTSD Symptoms, and Sleep Disturbances in a Sample of Firefighters with Duty-related Trauma Exposure

2021 ◽  
Author(s):  
Marie Roxanne Sopp ◽  
Tanja Michael ◽  
Johanna Lass-Hennemann ◽  
Shilat Haim-Nachum ◽  
Miriam J. J. Lommen
Keyword(s):  
Sleep Disturbances ◽  
Secondary Outcome ◽  
Secondary Outcome Measure ◽  
Ptsd Symptoms ◽  
Hair Cortisol ◽  
Trauma Severity ◽  
Work Related ◽  
Hair Samples ◽  
Average Work ◽  
Cortisol Levels

Several studies have found evidence of altered cortisol levels in patients with posttraumatic stress disorder (PTSD). Based on these findings, it is assumed that these patients may show signs of cortisol dysregulation after trauma. Posttrauma cortisol levels are thus considered a potential biomarker of PTSD. However, longitudinal studies using indicators of long-term cortisol secretion (such as hair cortisol concentrations; HCC) are scarce. The current study investigated prospective associations between HCC and PTSD symptoms in a sample of Dutch firefighters taking into account varying levels of work-related trauma severity. In addition, we assessed posttraumatic sleep disturbances as a secondary outcome measure to investigate whether effects generalize to this frequent comorbidity of PTSD. Three hundred seventy-one Dutch firefighters with a mean of 14.01 years of work experience were included in the analyses. Baseline assessment included the collection of hair samples and the measurement of work-related trauma severity, PTSD symptoms, and sleep disturbances. PTSD symptoms and sleep disturbance were re-assessed after six and twelve months. Multilevel analyses indicate a significant positive correlation between HCC and baseline PTSD symptoms in those with average or above-average work-related trauma severity. A similar pattern was evident for posttraumatic sleep disturbances at baseline. Moreover, higher HCC predicted more posttraumatic sleep disturbances after 6 months in participants with above-average work-related trauma severity. No other associations emerged for PTSD symptoms or posttraumatic sleep disturbances at six or twelve months. As such, our study supports the existence of a cross-sectional association between HCC and trauma symptoms, which may vary for different levels of subjective trauma severity. The longitudinal stability of this association should be reinvestigated by future research.

scholarly journals Hair cortisol-a method to detect chronic cortisol levels in patients with Prader-Willi syndrome

2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Hasanain Hamid Shukur ◽  
Yolanda B. de Rijke ◽  
Elisabeth F. C. van Rossum ◽  
Laith Hussain-Alkhateeb ◽  
Charlotte Höybye
Keyword(s):  
Linear Regression ◽  
Regression Model ◽  
Behavioral Problems ◽  
Linear Regression Model ◽  
Neurodevelopmental Disorder ◽  
Prader Willi Syndrome ◽  
Hair Cortisol ◽  
Hair Samples ◽  
Cortisol Levels

Abstract Background Prader-Willi syndrome (PWS) is a multisymptomatic, rare, genetic, neurodevelopmental disorder in adults mainly characterized by hyperphagia, cognitive dysfunction, behavioral problems and risk of morbid obesity. Although endocrine insufficiencies are common, hypocortisolism is rare and knowledge on long-term cortisol concentrations is lacking. The aim of this study was to evaluate long-term cortisol levels in PWS by measurements of hair cortisol. Methods Twenty-nine adults with PWS, 15 men and 14 women, median age 29 years, median BMI 27 kg/m2, were included. Scalp hair samples were analyzed for cortisol content using liquid-chromatography tandem-mass spectrometry. In addition, a questionnaire on auxology, medication and stress were included. For comparison, 105 age- and sex-matched participants from the population-based Lifelines Cohort study were included as controls. The mean hair cortisol between the groups were compared and associations between BMI and stress were assessed by a generalized linear regression model. Results In the PWS group large variations in hair cortisol was seen. Mean hair cortisol was 12.8 ± 25.4 pg/mg compared to 3.8 ± 7.3 pg/mg in controls (p = 0.001). The linear regression model similarly showed higher cortisol levels in patients with PWS, which remained consistent after adjusting for BMI and stress (p = 0.023). Furthermore, hair cortisol increased with BMI (p = 0.012) and reported stress (p = 0.014). Conclusion Long-term cortisol concentrations were higher in patients with PWS compared to controls and increased with BMI and stress, suggesting an adequate cortisol response to chronic stress. Hair cortisol demonstrate promising applications in the context of PWS treatment and disease management.

scholarly journals Preventing ectoparasite infestations reduces glucocorticoid concentrations in the hair of cows – short communication

2018 ◽  
Vol 66 (3) ◽  
pp. 390-393
Author(s):  
Sreten Nedić ◽  
Danijela Kirovski ◽  
Ivan Vujanac ◽  
Radiša Prodanović ◽  
Ljubomir Jovanović ◽  
...  
Keyword(s):  
Dairy Cows ◽  
Short Communication ◽  
Treated Group ◽  
Holstein Cows ◽  
Hair Cortisol ◽  
Hair Samples ◽  
Cortisol Levels

The aim of this study was to compare hair corticosteroid concentrations in ectoparasiticide-treated (n = 10) and non-treated (n = 12) Holstein cows. Animals in the treated group received cyfluthrin three times, on days 0, 28 and 56 of the experiment. Hair samples were collected from all cows on days 0, 21, 42, 63, and 84 of the experiment for the determination of cortisol and corticosterone concentrations using immunoassays. The respective hair cortisol concentrations in the treated group averaged 209.78, 165.10, 260.78, 177.44 and 183.11 ng/g, while in the non-treated group hair cortisol concentrations averaged 172.58, 243.58, 309.73, 199.75 and 207.09 ng/g. These results indicate that the control of ectoparasites reduced hair cortisol levels in dairy cows. The respective hair corticosterone concentrations in the treated group averaged 19.06, 22.95, 21.95, 21.60 and 24.84 ng/g and in the non-treated group the hair corticosterone concentrations averaged 17.28, 21.94, 34.05, 26.27 and 26.91 ng/g. The results suggest that longterm stress can be estimated better by the determination of hair cortisol rather than corticosterone concentrations.

Diving activity of a solitary wild free ranging bottlenose dolphin (Tursiops truncatus)

2008 ◽  
Vol 88 (6) ◽  
pp. 1153-1157 ◽  
Author(s):  
Bruno Díaz López ◽  
Julia Andrea Bernal Shirai ◽  
Alberto Bilbao Prieto ◽  
Paula Méndez Fernández
Keyword(s):  
Bottlenose Dolphin ◽  
Mixed Model ◽  
Linear Mixed Model ◽  
Bottlenose Dolphins ◽  
Western Coast ◽  
Small Areas ◽  
The North ◽  
Free Ranging ◽  
North Western ◽  
Frequent Presence

Solitary wild bottlenose dolphins and man frequenting the same small areas makes boat interaction more or less inevitable. Here we provide the first quantified data about solitary bottlenose dolphin diving behaviour in the presence and absence of boats. Over 110 hours were spent observing a solitary bottlenose dolphin within a 6 km2 bay on the north-western coast of Spain from April to August 2005. A generalized linear mixed model explaining 77.3% of the variability of duration of dives indicated that the animal did not vary its diving activity in function of the presence of boats. However, the length of dives was related with the behavioural events prior to dive. Dolphin activity was characterized by mean dive intervals (mean = 62.6 seconds) related to a predominance of foraging behaviour. Because of the frequent presence of boats and the manner in which they moved, the dolphin may have become accustomed to their presence. The data reported here could be used to implement precautionary management proposals that take into account the potential effects of boat presence on bottlenose dolphins.

scholarly journals Hair cortisol- a novel method to explore Prader-Willi syndrome.

2020 ◽  
Author(s):  
Hasanain Hamid Shukur ◽  
Yolanda B de Rijke ◽  
Elisabeth FC van Rossum ◽  
Laith Hussain-Alkhateeb ◽  
Charlotte Höybye
Keyword(s):  
Linear Regression ◽  
Regression Model ◽  
Behavioral Problems ◽  
Linear Regression Model ◽  
Neurodevelopmental Disorder ◽  
Prader Willi Syndrome ◽  
Hair Cortisol ◽  
Hair Samples ◽  
Cortisol Levels

Abstract Background: Prader-Willi syndrome (PWS) is a multisymptomatic, rare, genetic, neurodevelopmental disorder in adults mainly characterized by hyperphagia, cognitive dysfunction, behavioral problems and risk of morbid obesity. Although endocrine insufficiencies are common, hypocortisolism is rare and knowledge on long-term cortisol concentrations is lacking. The aim of this study was to evaluate long-term cortisol levels in PWS by measurements of hair cortisol. Methods: Twenty-nine adults with PWS, 15 men and 14 women, median age 29 years, median BMI 27 kg/m2, were included. Scalp hair samples were analyzed for cortisol content using liquid-chromatography tandem-mass spectrometry. In addition, a questionnaire on auxology, medication and stress were included. For comparison, 105 age- and sex-matched participants from the population-based Lifelines Cohort study were included as controls. The mean hair cortisol between the groups were compared and associations between BMI and stress were assessed by a generalized linear regression model. Results: In the PWS group large variations in hair cortisol was seen. Mean hair cortisol was 12.8±25.4 pg/mg compared to 3.8±7.3 pg/mg in controls (p=0.001). The linear regression model similarly showed higher cortisol levels in patients with PWS, which remained consistent after adjusting for BMI and stress (p=0.023). Furthermore, hair cortisol increased with BMI (p=0.012) and reported stress (p=0.014). Conclusion: Long-term cortisol concentrations were higher in patients with PWS compared to controls and increased with BMI and stress, suggesting an adequate cortisol response to chronic stress. Hair cortisol demonstrate promising applications in the context of PWS treatment and disease management.

scholarly journals Correlation analysis of cortisol concentration in hair versus concentrations in serum, saliva and urine.

2020 ◽  
Author(s):  
Lukasz Cieszynski ◽  
Jaroslaw Jendrzejewski ◽  
Piotr Wisniewski ◽  
Przemyslaw Klosowski ◽  
Krzysztof Sworczak
Keyword(s):  
Clinical Practice ◽  
Salivary Cortisol ◽  
Serum Cortisol ◽  
Individual Characteristics ◽  
Cortisol Concentration ◽  
Reference Ranges ◽  
Hair Cortisol ◽  
Free Cortisol ◽  
Hair Samples ◽  
Cortisol Levels

Abstract Background: Cortisol concentration is measured in blood, urine, and saliva samples. It has been recently proven that cortisol could be also detected in hair samples. Cortisol measurements in different samples have their own individual characteristics and clinical utility. We aimed to investigate the correlation between hair cortisol concentration and standard cortisol measurements used in clinical practice. Methods: Fifty adult volunteers with a negative history of endocrine disorders were enrolled into the study. Morning serum cortisol (MSC), evening serum cortisol (ESC), evening free salivary cortisol (EFSC), urine free cortisol (UFC) and hair cortisol were analyzed in all participants. Eventually, 41 volunteers were included into the study, whose cortisol concentration in the 1 mg overnight dexamethason suppression test (1mgONDST) were <50 nmol/l, and cortisol levels in serum, saliva and urine were within reference ranges. Hair cortisol concentration (HCC) was performed for 20 mg of hair strands of the proximal 1 cm hair segments. Results: HCC ranged from 0.3036 to 2.65 nmol/l/mg, and the average value was 0.8125±0.4834 nmol/l/mg. No significant correlations were found between HCC and MSC (rho=0.04419, p=0.7838), HCC and ESC (rho=-0.2071, p=0.1938), HCC and EFSC (rho=0.1005, p=0.532), and HCC and UFC (rho = 0.1793, p = 0.262). Conclusions : This work is another step in the discussion on the application of HCC determinations in clinical practice. Our results have showed no correlations between HCC and single point cortisol assessment in blood, saliva and urine in patients with reference cortisol levels. Keywords: Hair cortisol, Serum cortisol, Salivary cortisol, Urine cortisol, Cortisol assessment, Cortisol correlation

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